The Supplier Gives the External Diameter of the Candle Jar — Can I Use That for Wick Selection or Do I Need the Internal Diameter?

The Supplier Gives the External Diameter of the Candle Jar — Can I Use That for Wick Selection or Do I Need the Internal Diameter?

 

Clear 150 g jar (states outer 7 cm): ₹94.40 each C1 ₹5.90 · C2 ₹9.44 · Braided ₹12.00 a wick Weighing Scale ₹354.00
Outside vs inside · measure before you wick
Get the inside diameter your wick actually works on, then bracket three rungs.
★★★★★
"The jars were of good quality"
Soumili GopeVerified buyer · Mar 2026
Clear Glass Jar with Golden Lid (150 gram)
★★★★★
"Very good"
Tina Lynette Lazaro MogantiVerified buyer · Dec 2025
Black Matte Glass Jar
★★★★★
"Quality wick, works very well"
AshwiniSep 2025
Eco Candle Wicks
★★★★★
"This bamboo wick holder doesn’t exert any pressure on the wicks… and it is a very useful product 👌🏻👌🏻.."
Lalitha JaganAug 2024
Bamboo Wick Holder
★★★★★
"Soy wax quality is the best, which ever products ordered were properly packed and delivered as early as possible, timely response to the inquiries. Good service"
Jaya SawlaniVerified buyer · Nov 2025
Luxury Soy Wax CSI 464 (Flakes Form) For Container Candles
★★★★☆
"For candle making and new beginner this is very helpful, i came to know about them from Sosa candle, Sonal guide us in youtube about product materials and everything she suggested this, I trusted her and gave a try, and it is authentic product and other materials too. Sometimes it happens that all materials didnt reach me, they take the responsibility and send me. The team is co-operative in nature and friendly too. If i ordered liquid colors or fragrance that too packed so well that there is no leakage also my packaged item where misplaced by delivery boy i guess (i didn't remember properly) they sent it again they took all that responsibility that gains the trust. Only i felt little costly during checkout when its kg amount calculated (ho sakhe todha kam kar do,haha). Overall had great experience with them. Thankyou so much 👍😊"
JinalOct 2025
Ceramic Jar for Candle Making
★★★★★
"The jars were of good quality"
Soumili GopeVerified buyer · Mar 2026
Clear Glass Jar with Golden Lid (150 gram)
★★★★★
"Very good"
Tina Lynette Lazaro MogantiVerified buyer · Dec 2025
Black Matte Glass Jar
★★★★★
"Quality wick, works very well"
AshwiniSep 2025
Eco Candle Wicks
★★★★★
"This bamboo wick holder doesn’t exert any pressure on the wicks… and it is a very useful product 👌🏻👌🏻.."
Lalitha JaganAug 2024
Bamboo Wick Holder
★★★★★
"Soy wax quality is the best, which ever products ordered were properly packed and delivered as early as possible, timely response to the inquiries. Good service"
Jaya SawlaniVerified buyer · Nov 2025
Luxury Soy Wax CSI 464 (Flakes Form) For Container Candles
★★★★☆
"For candle making and new beginner this is very helpful, i came to know about them from Sosa candle, Sonal guide us in youtube about product materials and everything she suggested this, I trusted her and gave a try, and it is authentic product and other materials too. Sometimes it happens that all materials didnt reach me, they take the responsibility and send me. The team is co-operative in nature and friendly too. If i ordered liquid colors or fragrance that too packed so well that there is no leakage also my packaged item where misplaced by delivery boy i guess (i didn't remember properly) they sent it again they took all that responsibility that gains the trust. Only i felt little costly during checkout when its kg amount calculated (ho sakhe todha kam kar do,haha). Overall had great experience with them. Thankyou so much 👍😊"
JinalOct 2025
Ceramic Jar for Candle Making
Reviews collected and published through Judge.me on candlemakingsuppliesindia.store. They are general reviews of the products named on each card, not assessments of the advice set out below. Wording is unedited.
Shop the Clear 150 g jar — ₹944.00 for 10 Send us your inside measurement on WhatsApp
✓ Prices verified 26 September 2026, out-of-stock items flagged ✓ MSDS and IFRA documentation on request on WhatsApp ✓ Raw materials only — CSI does not sell finished candles
CSI Jar & Container Guides · Diameter & Wick
A supplier's diameter is almost always the outside of the glass. Your wick only ever melts the inside. Here is how big that gap is, what our own listings state, and five ways to measure the number that matters.
+23.5%
how far a 7 cm outside figure over-reads the melt pool with 3.5 mm walls (worked example) · CSI live pricing, September 2026
Quick answers — read this first
Can I pick a wick from the external diameter? No. The wick has to melt the pool inside the glass. The outside figure includes two thicknesses of wall, and on a 7 cm jar with 3.5 mm walls it over-reads the pool area by 23.5%.

How big is the error? On a jar listed at 7 cm outside, the outside figure overstates the pool by about 12.5% with 2 mm walls and 36.1% with 5 mm walls. On a 6 cm jar the error is larger; on a 10 cm jar, smaller.

How do I get the internal diameter? Best: calliper inside jaws at the height the pool will sit. Otherwise: outside minus two walls (straight jars only), a steel rule across a straight opening, or water-rise, where grams of water per centimetre of depth give you the inside area.

Do CSI listings give the inside diameter? No. Of 72 container listings, 7 say "outer", 14 give an unspecified "diameter", 20 give a "width" and 31 give neither. None states an internal diameter.
The short answer
The rule: wick for the internal diameter at the height the melt pool sits. The external figure is right for lids, boxes and wick-holder bars, and wrong for the wick.
The error: outside diameter minus two walls is the inside; the pool area goes with the square, so a few millimetres of glass become 12% to 36% of pool area on a 7 cm jar.
The method: calliper inside at pool height; or outside minus 2 × wall; or water-rise (1 cm of water in a 6.3 cm jar weighs about 31.2 g). Measure three jars; use the smallest figure.
Then: bracket three wick rungs in the measured jar and let the burn decide. Measuring tells you where to start; it never tells you the answer.
Shop: Clear 150 g jar (states outer) · White Matte (states width) · Black Shiny 6 cm · Weighing Scale · Eco C1/C2 · Cotton Braided
In this guide
The same "7 cm" jar, three wall thicknesses, three different pools Top view, drawn to scale, 1 cm = 26 px. The outer edge of each dark ring is the listed 7 cm outside diameter; the dark ring is the glass wall; the pale disc is the melt pool your wick has to reach. inside 6.6 cm 34.2 cm² pool wall 2 mm "7 cm" (38.5 cm²) over-reads +12.5% inside 6.3 cm 31.2 cm² pool wall 3.5 mm "7 cm" (38.5 cm²) over-reads +23.5% inside 6.0 cm 28.3 cm² pool wall 5 mm "7 cm" (38.5 cm²) over-reads +36.1% Pool area, to scale (1 cm² = 4 px) outside 7.0 38.5 cm² inside 6.6 34.2 cm² inside 6.3 31.2 cm² inside 6.0 28.3 cm² Wall thicknesses are illustrative. No CSI listing states a wall thickness or an inside diameter: measure yours at the height the pool will sit.
One outside figure, three possible pools. A jar listed at 7 cm could be 6.6 cm, 6.3 cm or 6.0 cm inside depending on the glass, and because area goes with the square, the outside figure over-reads the pool by 12.5% to 36.1%. The wick only ever sees the pale disc.
States "outer diameter 7cm" · ₹94.40 a jar
Clear 150 g jar: measure the inside before you wick it
Water-rise method · ₹354.00
Weighing Scale: grams of water become an inside diameter
WhatsApp +91 7397976926
Send us your inside measurement; we suggest rungs to test
Straight answer
The supplier gives the external diameter of the candle jar. Can I use that for wick selection, or do I need the internal diameter?
You need the internal diameter, measured at the height the melt pool will sit. A wick's job is to melt a pool of wax out to the glass; the glass itself does not melt, so its thickness is not part of the job. The external figure includes the wall twice, and because pool area goes with the square of the diameter, a small gap becomes a big one: on a jar listed at 7 cm outside, 2 mm walls leave 6.6 cm inside and the outside figure over-reads the pool by 12.5%; 5 mm walls leave 6.0 cm and it over-reads by 36.1%. Wick for the outside figure and you tend to over-wick: a pool that runs deep, a tall flame and a hot jar. Get the inside with a calliper's inside jaws, or subtract two measured walls from the outside on a straight jar, or use water-rise on a scale. Measure three jars and wick for the smallest. Then bracket three wick rungs and burn-test, because even a perfect inside figure only tells you where to start.
One line: the outside diameter describes the glass; the inside diameter describes the candle, and the wick only ever works on the candle.
Measure a jar that tells you it is quoting the outside. The Clear Glass Jar with Golden Lid (150 gram) states "outer diameter 7cm" and a 6.5 cm base: ₹944.00 for 10 (₹94.40 each, in stock on 26 September 2026). Three to measure, nine for a three-rung bracket, with one spare after the measuring jars are reused.
Buy a pack of 10 — ₹944.00

How far the outside figure over-reads the pool

A millimetre of glass on each side looks like nothing. Squared, it is a tenth of your pool.

The wick melts a disc of wax. The disc's area is π × r², using the inside radius. The outside diameter adds two wall thicknesses to that radius's diameter, and the area error grows faster than the length error. For a jar listed at 7 cm outside, with a straight wall, this is what different glass does:

7 cm outside diameter · pool area by wall thickness · worked example
Inside = outside − 2 × wall; pool area = π × (inside ÷ 2)²
Wall Inside diameter Real pool area Area if you use 7 cm Outside figure over-reads by
0.2 cm 6.6 cm 34.21 cm² 38.48 cm² 12.5%
0.3 cm 6.4 cm 32.17 cm² 38.48 cm² 19.6%
0.35 cm 6.3 cm 31.17 cm² 38.48 cm² 23.5%
0.4 cm 6.2 cm 30.19 cm² 38.48 cm² 27.5%
0.5 cm 6.0 cm 28.27 cm² 38.48 cm² 36.1%

Wall thickness varies by mould, glass type and style: heavy "apothecary" and luxury jars tend to be thick-walled, pressed tumblers thinner. The wall figures above are a range to think with, not a claim about any listing. What they show is that the outside number is not a slightly rough version of the inside number; it is a different number, and the gap depends on glass you cannot see in a photograph.

The error is worst on small jars

The same walls take a bigger share of a small jar. Using stated figures from CSI's own listings and two illustrative walls:

Outside figure vs inside, by jar size · CSI listing figures, illustrative walls
How much the stated figure over-reads the pool at 3.5 mm and 5 mm walls
Stated figure CSI listings using it 3.5 mm walls: inside · over-read 5 mm walls: inside · over-read
6 cm Shiny 120 g jars, Shot Glass jar ("6 cm") 5.3 cm · 28.2% 5 cm · 44.0%
7 cm Matte 200 ml ("width 7"), 150 g jars ("outer 7"), Iridescent 300 g ("7") 6.3 cm · 23.5% 6 cm · 36.1%
10 cm Apothecary Dome Lid ("outer rim 10") 9.3 cm · 15.6% 9 cm · 23.5%

On a 6 cm jar, 5 mm walls mean the outside figure over-reads the pool by 44.0%; on a 10 cm jar, the same walls give 23.5%. That is one reason small gift jars are easy to over-wick: the maker wicks for "6 cm" and the candle may be 5 cm across.

What over-wicking from the outside figure looks like

If you choose a wick expecting a 38.5 cm² pool and the jar gives you 31 cm², the wick is effectively a size too large for the jar. Common signs: the pool reaches the glass well inside the 3 to 4 hours many makers aim for on a first burn, the pool runs deeper than about 1 cm, the flame stands tall or flickers, soot marks the glass, and the jar runs hot in the last third. These are tendencies; a burn test on your own wax and oil is the only verdict. The less common opposite, under-wicking, happens when a maker "corrects" by guessing a wall and overshoots.

Mistake: treating "diameter 7 cm" on a listing as a wick spec, and ordering 100 of one wick for it. Why it fails: the figure could be the outside, the rim, the base or the widest point, and says nothing about the wall. Fix: order a pack of jars, measure the inside at pool height, and bracket wicks in the measured jar before ordering wicks in bulk.

What CSI's 72 container listings actually state

We read every one. Not one gives you the inside.

We went through all 72 container listings on our store, from 40 ml mini jars and tealight cups to 700 g apothecary jars, and recorded how each describes its width. This is our own catalogue on 26 September 2026, so we have no reason to flatter it.

CSI container listings by diameter wording · verified 26 September 2026
What the page says, how many say it, and what you can and cannot take from it
Wording on the page Listings (in stock) Examples What it tells you What it does not
"Outer diameter" / "outer rim" plus a base diameter 7 (6) Clear Glass Jar with Golden Lid (150 gram): rim 7, base 6.5; coloured 150 g jars; Apothecary Dome Lid: rim 10, base 10 The figure is the outside, and the jar narrows or is straight Wall thickness, so the inside; on the Apothecary jar, which of its two sizes the figures describe
"Diameter", unspecified 14 (11) Shiny 120 g jars: 6 cm; Shot Glass jar: 6 cm; Green Iridescent 300 g: 7 cm; tealight cups A size class Whether it is outside, inside, rim or widest point
"Width" 20 (13) White Matte and its sisters: "Height 8 cm width 7 cm" Almost certainly an outside measure Outside or inside, wall thickness, straight or tapered
No diameter or width 31 200ml Salsa lug-cap jars, 70 g votives, borosilicate 600 g, tins ("6 cm x 4 cm", axes unnamed) Capacity only, if that Anything about the pool
Internal diameter 0 — — Not stated on any CSI listing

So 43% of our container listings give no width at all, and the rest give a figure that is outside or unlabelled. Two details matter for wicking. The 150 g jars state a 7 cm rim and a 6.5 cm base: an outside that narrows by 5 mm toward the bottom, so the inside probably does too, and the pool may get smaller as the candle burns down (the implications are in the narrowing-jar guide). And the Apothecary Glass Candle Jar with Dome Lid gives one set of dimensions, rim 10 cm, base 10 cm, height 10.8 cm, for two sizes, 500 g (₹212.40) and 700 g (₹250.00), so they cannot describe both sizes exactly; ask us which before you rely on either.

Argued against our own interest: we could print an inside diameter on every listing from a single sample. We have not, because one sample is not a spec, and a figure you trust is worse than a figure you know to check. Until we publish measured insides, treat every diameter on our store, and every other supplier's, as outside or unknown.

Five ways to get the inside diameter

One needs a calliper. Two need only a rule. One needs a scale and a glass of water.
Getting from outside to inside · methods compared
Tools, typical precision and where each one fails
Method Tools Typical precision Works for Fails when
1. Calliper inside jaws at pool height Vernier or digital calliper Better than 0.5 mm Any jar you can reach into to the pool height The opening is narrower than the pool (shoulder, lug neck)
2. Outside minus two walls Calliper for outside and rim wall About 0.5 mm if walls are even Straight-sided jars with no lip A rolled lip, a thicker rim, a taper, a heavy base corner
3. Steel rule across the opening Steel rule About 1 mm Straight jars, reading at the rim Tapered jars (reads the top only) and shoulders
4. Circumference, then minus walls Paper strip, rule, calliper for wall About 1 mm Reading the outside at a chosen height on curved jars You do not know the wall at that height
5. Water-rise on a scale Scale reading 1 g, tape, water About 1 mm on 6 to 8 cm jars Any jar, any height, even behind a shoulder The section is not straight over the depth you fill

Method 1: the calliper, and where to hold it

Open the inside jaws against the glass at the height the pool will sit on the first burns: about 1 to 2 cm below your fill line. Rotate the calliper a quarter turn and read again; glass jars are rarely perfectly round, and the smaller reading is the honest one. Repeat at the middle and near the base if the jar is not straight. CSI does not sell callipers; a basic one from a hardware shop is enough.

Method 2: outside minus two walls

Measure the wall across the rim with the calliper's outside jaws. Inside = outside − 2 × wall. Worked example: outside 7.0 cm, wall 3.5 mm, inside 6.3 cm. It is fast and it is where most errors come from: many jars have a thickened or rolled rim, so the rim wall is not the body wall, and the base corner is thicker still. Use it only on plain straight tumblers, and cross-check with method 3 or 5.

Methods 3 and 4: rule and paper strip

A steel rule laid across the opening, zero on one inner edge, reads a straight jar to about a millimetre. For a curved jar, wrap a paper strip round the outside at pool height, mark the overlap, measure the length and divide by π (3.14) for the outside diameter at that height; then subtract two walls. It is the way to use a listing like "rim 7, base 6.5" properly: measure the outside at the height you care about instead of guessing between the two.

Measure three, wick for the smallest
Mass-produced glass varies between pieces and batches. Measure at least three jars from a pack and wick-test in the one with the smallest inside at pool height: a wick that reaches the glass in the narrowest jar is less likely to over-heat it. Batch drift across a large order is covered in the batch-variation guide.

The water-rise table: grams per centimetre to inside diameter

Water weighs about a gram per millilitre. That turns your scale into an inside calliper.

In a straight section, each centimetre of water depth weighs the inside area in grams, because 1 ml of water is about 1 g and area × 1 cm = volume. So: tare the jar, add water to a first tape mark (say 1 cm above the floor, to clear any rounded base corner), note the reading, add water to a second mark exactly 2 cm higher, and note the grams added. Divide by 2 for grams per centimetre, then find the diameter below.

Water-rise lookup · 1 ml of water ≈ 1 g · straight section
Grams of water per centimetre of depth, and per 2 cm, for each inside diameter
Grams per 1 cm of depth Grams per 2 cm of depth Inside diameter
19.6 g 39.3 g 5 cm
23.8 g 47.5 g 5.5 cm
28.3 g 56.5 g 6 cm
31.2 g 62.3 g 6.3 cm
33.2 g 66.4 g 6.5 cm
38.5 g 77.0 g 7 cm
44.2 g 88.4 g 7.5 cm
50.3 g 100.5 g 8 cm
63.6 g 127.2 g 9 cm
78.5 g 157.1 g 10 cm

Worked example: 60.4 g of water between two marks 2 cm apart is 30.2 g per centimetre, which sits between the 6.0 and 6.3 cm rows: the inside is about 6.2 cm. The formula, if you prefer: inside diameter = 2 × √(grams per cm ÷ π). A 1 g error on a 2 cm rise moves a 6 to 7 cm answer by about half a millimetre, and a tape mark 1 mm off moves it by more, so read to the gram, keep the marks level and repeat once.

Mistake: filling from the floor and dividing the total grams by the total depth. Why it fails: bases are often rounded or domed inside, so the first centimetre holds less water and drags the answer down. Fix: measure the rise between two marks above the base, at the height the pool will sit. Dry the jar completely before it sees wax.

The same scale gives you the fill weight: water to your fill line, times a rule-of-thumb factor for wax, then a test pour, as set out in the fill-weight hub.

When the outside diameter is the right number

The external figure is not useless. It answers different questions.

Keep the outside diameter for everything that sits on or around the jar. Keep the inside diameter for everything that happens in the wax.

Which diameter for which job
Outside for fit and packing; inside for the burn
Job Use Why
Wick choice and pool area Inside, at pool height The wick melts wax, not glass
Double or triple wick spacing Inside Spacing is set by the pool each wick must cover
Fill weight and net quantity Neither: weigh water to your fill line Diameter and height miss base shape and shoulders
Wick-holder bars that rest on the rim Outside at the rim The Steel Wick Holder page says it "fits most jar diameters (up to 9 cm wide)"; the Wick Centering Device page, openings "less than 4"" (the pages' wording)
Lids, labels, boxes, shipping Outside, and rim for lids These wrap the glass

Watch for wick pages that quote a size, too. The Cotton Braided Wicks Ready Made page says "engineered for large-diameter candles exceeding 8 cm" and does not say inside or outside. Treat it as positioning: a hint of which end of the range the wick sits in, never a fitting rule.

Jars, tools and wicks for measuring and testing

Chosen to show each kind of diameter wording on our store, plus the scale and the wick rungs the next step needs. Selection is on stated wording, price and stock on 26 September 2026; CSI has no burn data for any jar.

1
jar · says "outer" · 150 g apothecary
Clear Glass Jar with Golden Lid (150 gram)
The clearest case on our store of a listing that tells you it is giving the outside: "outer diameter 7cm" at the rim and "base diameter approximately 6.5cm". The page's structured data calls it thick-walled, so the inside could be well under 7 cm, and 5 mm narrower again at the base. The page states "Safe for hot pour up to 85°C" (its wording). It also calls the jar both a "curved silhouette" and "straight-sided", which is one more reason to measure at two heights. For makers who want a lidded jar with a stated hot-pour figure. Limitation: coloured versions at ₹107.00 a jar state only a with-lid height.
Pack Price Per jar What it covers
Pack of 10 ₹944.00 ₹94.40 measure 3, then a nine-candle, three-rung bracket
Pack of 20 ₹1,888.00 ₹94.40 the bracket plus a burn-down jar for each rung and spares
₹94.40 per jar at 10 or 20. Buy a pack of 10 — ₹944.00
2
jar · says "width" · 8 × 7 cm family
White Matte Glass Jar
States "Height 8 cm width 7 cm" and "a fill weight of 200 ml". "Width" on a round jar almost certainly means the outside, but the page does not say, and it gives no wall thickness. The series worked example treats it as 7 cm outside with walls of about 3.5 mm, an inside of about 6.3 cm: an assumption to replace with your own calliper reading. Same wording and prices on 12 in-stock matte, glossy and frosted sisters on 26 September 2026; Pink Matte, Frosted Brown and Orange Frosted are out of stock. Limitation: no numeric heat figure ("withstand high heat").
Pack Price Per jar What it covers
Pack of 5 ₹354.00 ₹70.80 measure 2, burn 3 in a C1/C2/braided bracket
Pack of 10 ₹708.00 ₹70.80 a full nine-candle bracket plus one spare
₹70.80 per jar at 5 or 10. Buy a pack of 5 — ₹354.00
3
jar · says "diameter" · 6 cm, 120 g
Black Shiny Glass Jar with Golden Lid
States "6 cm diameter, 6.5 cm height" and "Capacity: 120 gm", with no word on inside or outside. On a 6 cm jar every millimetre of wall matters more: with 3.5 mm walls the outside figure over-reads the pool by 28.2%. Amber, Pink, Red, Green, Navy Blue and Purple versions carry the same figures; Amber's and Pink's text is copied from the Black listing, so confirm colour and lid on WhatsApp. The page states no heat figure. For small gift candles. Limitation: Red, Green, Navy Blue and Purple are sold singly at ₹50.00.
Pack Price Per jar What it covers
Pack of 1 ₹47.20 ₹47.20 one jar to measure before buying more
Pack of 5 ₹236.00 ₹47.20 measure 2, bracket C1/C2 in 3
₹47.20 per jar at 1 or 5 (Black). Buy a pack of 5 — ₹236.00
4
tool · the water-rise method needs it
Candle Making Weighing Scale
The water-rise method turns grams into an inside diameter without reaching into the jar, and it needs a scale that reads single grams. The page describes a digital scale in "grams or ounces" with "simple one-button operation" and states no maximum capacity or reading step. Argued against our own interest: if your kitchen scale reads 1 g and tares, it does this job as well as ours.
Item Price Per unit What it covers
Single ₹354.00 ₹354.00 water-rise, fill-line and finished-candle weighings
One scale covers every weighing in this guide. Buy the scale — ₹354.00
5
wick · the three rungs to test once you know the inside
Eco C1 / C2 and Cotton Braided Wicks
Knowing the inside diameter tells you which rungs to test, not which wick wins. Eco C1 and C2 are ₹5.90 and ₹9.44 a wick at every pack size; Cotton Braided Wicks Ready Made are ₹12.00 a wick at every pack size, and that page says they are "engineered for large-diameter candles exceeding 8 cm" without saying inside or outside. No CSI wick page gives an inside-diameter range (one loose-wick listing names "2 inch diameters" without saying inside or outside), which is why we never give you one either: bracket and burn. Limitation: a jar near 10 cm inside may need a two-wick layout in the test; see the 1, 2 or 3 wicks guide.
Pack Price Per wick What it covers
C1 / 10 ₹59.00 ₹5.90 lower rung, three candles
C2 / 10 ₹94.40 ₹9.44 middle rung, three candles
Cotton Braided / 10 ₹120.00 ₹12.00 upper rung, three candles
All three rungs: ₹273.40. Buy C1/C2 — from ₹59.00
When the right purchase is nothing: if you already own the jars, a rule and a kitchen scale that reads 1 g, you can get the inside diameter tonight with methods 3 and 5. Buy from us only when you are ready to bracket wicks.

From the inside figure to a wick test

The inside diameter tells you which three wicks to test. The burn tells you which one stays.

Once you have a measured inside, the next step is the same whichever jar it is: choose three wick rungs that sit either side of your best guess, pour three candles on each, and judge them over a full burn. The measuring guards against the most common mistake, starting from a figure 12% to 36% too big, but it does not replace the test. How to choose the first three rungs for a straight jar is set out in the first-three-wicks guide, and why diameter, not ml, drives the choice in the diameter-and-wick hub.

1
Measure three jars at pool heightCalliper or water-rise, about 1 to 2 cm below your fill line. Write down all three; take the smallest.
2
Measure again at the middle and near the baseIf the inside changes by more than a millimetre or two, the jar tapers: note it, because the last third will burn differently.
3
Pick three rungsC1, C2 and Cotton Braided Wicks Ready Made make a simple three-rung ladder from CSI's ready-made wicks; wooden wicks are a separate family to bracket on their own. They are starting points to test, not answers.
4
Pour nine candlesThree per rung, same wax, oil and load, into the measured jars. Weigh each finished candle as you go.
5
Burn 3 to 4 hours and logAfter your usual cure: pool diameter each hour (does it reach the glass, and when), pool depth (0.5 to 1 cm is a common aim), flame height, soot.
6
Burn the likely winner downIn sessions to about 1 cm of wax left, watching the final third. Never unattended; stop if the flame grows or the glass runs hot.
Measure-then-bracket kit · CSI live pricing, 26 September 2026
Three jars measured, nine candles poured on three rungs: ₹1,984.80
Item Buy Price Role
Clear Glass Jar with Golden Lid (150 gram) Pack of 10 ₹944.00 3 measured (then dried and reused), 9 poured, 1 spare
Eco C1 + C2 + Cotton Braided 10 each ₹273.40 Three rungs, three candles each, spares for a retest
Luxury Soy Wax CSI 464 1 kg + 500 g ₹767.40 Nine 150 g candles at 8% need 1,242 g of wax (worth ₹630.19); 1.5 kg leaves about 250 g for top-ups and pitcher loss
Your fragrance oil 108 g already owned 12 g per candle at 8%
Total new spend ₹1,984.80 ₹2,338.80 with the scale; ₹1,748.80 using a pack of 10 White Matte jars instead

A note on the 150 g jar and its load: its page's "hot pour up to 85°C" wording sits inside CSI 464's stated 80°C to 90°C pour range, and the lower of the two limits governs, so pour at 80°C to 85°C into that jar. CSI 464's page states a fragrance load of up to 10%; that is a ceiling, not a target, and the wick test is best run at the load you will sell. Wax is ₹0.51 a gram at 1 kg and the same per gram up to 10 kg. Costs exclude labour, freight, packaging and GST.

If you change the oil later
A wick bracketed in the right jar can still shift with a different fragrance. Change one thing at a time; see choosing a wick after changing fragrance oil.
Diwali is 8 November 2026, 43 days from 26 September 2026. Measure this week, pour the nine-candle bracket by early October, and you have time for a burn-down before a production pour. Send us your inside measurement and we will suggest which CSI jars and rungs to sample, with stock and a dispatch date.
WhatsApp your measurements
The CSI principle
Wick for the wax, not the glass.
Every diameter on a listing, ours included, is outside or unlabelled. Measure the inside at pool height, wick-test in the narrowest jar, and keep the outside figure for lids and boxes.
"The glass does not melt. Take it out of the number before you choose a wick."
— CandleMakingSuppliesIndia
Why trust this guide

CandleMakingSuppliesIndia sells the jars, wicks, scale and wax named here, and does not sell finished candles. This page audits our own 72 container listings and reports that none states an inside diameter, that 31 state no width at all, and that one gives a single set of dimensions for two sizes. We would rather you measured than trusted us.

Every price and per-jar or per-wick figure was verified on CSI's live store on 26 September 2026; every pack in a pick table is in stock on that date. Diameter, capacity and heat wording is quoted from the product pages, and the counts come from reading every listing.

Wall thicknesses in the tables are illustrative; pool areas are π × r²; the water-rise method relies on 1 ml of water weighing about 1 g; "measure three, wick for the smallest" and the kit are editorial judgement; full pool in 3 to 4 hours and 0.5 to 1 cm pool depth are common rules of thumb. For bulk pricing, GST invoicing, and MSDS and IFRA documentation on request, message us on WhatsApp at +91 7397976926.

Frequently asked questions

Should I use the inside or outside diameter of a candle jar to choose a wick?
The inside, measured at the height the melt pool will sit. The outside figure includes two walls, and on a 7 cm jar it over-reads the pool area by about 12.5% to 36.1% for walls of 2 to 5 mm.
How do I find the internal diameter of a glass jar without callipers?
Lay a steel rule across a straight jar's opening, or use water-rise: weigh the water between two marks 2 cm apart, halve it for grams per centimetre, and read the diameter from a table (31.2 g per cm is about 6.3 cm).
How thick is the glass on a candle jar?
It varies by mould and style, commonly a few millimetres, thicker at the base and often at the rim. No CSI listing states a wall thickness; measure across the rim with a calliper, and check the body with the water-rise method.
Is the diameter on a candle jar listing internal or external?
Usually external or unlabelled. On CSI's 72 container listings, 7 say "outer", 14 say "diameter" without saying which, 20 give a "width" and 31 give neither; none states an internal diameter.
What happens if I choose a wick for the external diameter?
You tend to over-wick: the pool reaches the glass early and runs deep, the flame is tall and may soot, and the jar can run hot in the last third. Measure the inside and bracket three wicks instead.
Does a 7 cm candle jar need a C1 or C2 wick?
No one can tell you from "7 cm". Measure the inside at pool height, then test C1, C2 and a larger rung such as Cotton Braided side by side with your wax and oil, and keep the one that reaches the glass in about 3 to 4 hours without running hot.
Measure the inside, then test
Ten jars that state "outer", three wick rungs and 1.5 kg of wax: ₹1,984.80.
Measure three jars at pool height and take the smallest; pour nine candles on C1, C2 and Cotton Braided; burn, log, and burn the winner down. You will know the inside diameter to the millimetre and which rung it wants, instead of a number off a listing.
Start with the Clear 150 g jar Send us your measurement
Continue the read — jar diameter and wick selection
Editorial standards & sources
About this guide: part of CSI's jar-diameter and wick-selection cluster: why a supplier's external diameter cannot be used for wick selection, how far it over-reads the melt pool at different wall thicknesses and jar sizes, an audit of how all 72 CSI container listings describe width, five ways to get the internal diameter (including a water-rise lookup table), when the external figure is the right one, and a measure-then-bracket kit.

Customer reviews: The six reviews at the top of this page are genuine, published Judge.me reviews left by CSI customers on the product pages named on each card — Bamboo Wick Holder, Black Matte Glass Jar, Ceramic Jar for Candle Making, Clear Glass Jar with Golden Lid (150 gram), Eco Candle Wicks, Luxury Soy Wax CSI 464 (Flakes Form) For Container Candles. They are general product reviews, not assessments of the container advice on this page. Names, star ratings, dates and products are as recorded by Judge.me and wording is unedited. "Verified buyer" appears only on reviews Judge.me recorded as verified — Soumili Gope, Tina Lynette Lazaro Moganti, Jaya Sawlani. The reviews from Ashwini, Lalitha Jagan, Jinal are published but not recorded as verified, and carry no badge. Reviews below five stars are included as published, not filtered out.

Figures verified 26 September 2026, CSI live pricing: Clear Glass Jar with Golden Lid (150 gram) Pack of 10 ₹944.00, Pack of 20 ₹1,888.00 (₹94.40 per jar); coloured 150 gram jars ₹107.00 per jar (Amber out of stock); White Matte Glass Jar Pack of 5 ₹354.00, Pack of 10 ₹708.00 (₹70.80 per jar); Black Shiny Glass Jar with Golden Lid Pack of 1 ₹47.20, Pack of 5 ₹236.00; Red, Green, Navy Blue and Purple Shiny ₹50.00 single; Apothecary Glass Candle Jar with Dome Lid 500 gm ₹212.40, 700 gm ₹250.00; Candle Making Weighing Scale ₹354.00; Eco Candle Wicks Thin (C1) 10 ₹59.00; Thick (C2) 10 ₹94.40; Cotton Braided Wicks Ready Made 10 ₹120.00; Luxury Soy Wax CSI 464 500 g ₹260.00, 1 kg ₹507.40. Per jar = pack price ÷ units; per wick = pack price ÷ wicks; two decimals.

Non-price figures: listing counts (7 outer, 14 unspecified diameter, 20 width, 31 neither, 0 internal) are from reading all 72 CSI container listings on 26 September 2026. Wall thicknesses of 2 to 5 mm are illustrative; pool area = π × r² on the inside radius; 1 ml of water ≈ 1 g. Full pool in 3 to 4 hours and 0.5 to 1 cm pool depth are common rules of thumb. Load is a percentage of total candle weight (150 g at 8% = 12 g oil + 138 g wax). Costs exclude labour, freight, packaging and GST.
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