I Have a Working Wick for My 200 g Candle but Want to Create a 300 g Version in a Wider Jar — Why Can’t I Simply Choose a Proportionally Larger Wick?

Why "proportionally larger" sounds right

The instinct is reasonable. A bigger candle burns more wax, so surely it needs a bigger flame, and 50% more wax should mean roughly 50% more wick. The trouble is what "more wax" means to a flame. A wick does not burn the candle all at once. It burns the top layer, through a pool whose size is set by the jar's inside diameter, session after session, until the wax runs out. Extra grams below the surface do not make the top layer any wider; they make the candle last longer.

So the question a wick answers is: can one flame, or two, melt this surface to the glass at a sensible depth, with this wax and this oil, without running too hot as the candle burns down? Weight enters that question only through the jar's shape. If the extra weight went into width, the pool grew. If it went into height, the pool did not, but the candle now has a longer, deeper life, which changes the late burn rather than the first. How tall-narrow and short-wide jars behave differently is the physics in the tall-narrow versus short-wide post; this page is about the number you were going to scale.

There is a second, practical problem. "Proportionally larger" assumes wicks come in a continuous range you can scale. They don't. A wick series is a set of steps, and CSI's range is short: the pre-tabbed Eco wicks come as Thin (C1) and Thick (C2), the page states no length, width or jar range for either, and the next CSI rung is Cotton Braided, described for candles "exceeding 8 cm". Even if 1.5 times your wick were the right answer, no listing could sell it to you.

The mismatch table: +50% grams against pool area

Every row below holds a 200 g candle and a 300 g candle of the same wax and load. Only the inside diameters change. Pool area is π × r² on the inside radius; the wax-height column uses the fact that, for a straight-sided jar, height scales with weight divided by area. These are geometry, not burn predictions.

Read down the "Pool area" column and the instruction "make the wick 50% bigger" falls apart. In the first row the right change may be no change at all, because the pool is the same. In the last row the pool more than doubles, and a single wick 50% "bigger" would likely leave wax on the glass. Only the 8.57 cm row agrees with the proportional rule, and only because that is the diameter at which the extra weight goes entirely into width, leaving the wax the same depth.

Two-wick builds change the comparison again. In a 9.0 cm inside jar, two wicks each face 31.81 cm² of pool, less than the 38.48 cm² your single wick faced at 7.0 cm. That is why a bigger candle sometimes wants two smaller wicks rather than one larger one, and why the bracket below includes a two-wick arm. How one larger wick compares with two smaller ones at 8.5 cm is the one-or-two-wicks post.

Where the extra 100 g goes: height or width

Put numbers on the three candles in the diagram. At a rule-of-thumb 0.9 g of wax per ml (commonly used candle-maker figures run about 0.86–0.9 times the water weight; weigh your own), 200 g in a 7.0 cm inside jar stands about 5.77 cm deep. The same jar width with 300 g stands about 8.66 cm deep. A 9.0 cm inside jar holds 300 g at about 5.24 cm, slightly shallower than the original 200 g.

The first-burn times are the very rough rule of thumb of about one hour per 2.5 cm of width, nothing more. Candle B is the trap in the other direction. Its pool is the same, so the old wick is the right first guess, but its life is half again as long and the last few centimetres sit deeper in the glass, where heat commonly builds. That is a full-life question, not a wick-size question; the late-burn behaviour of tall and short jars belongs to the paired tall-narrow and short-wide plan. Candle C is where the wick question really changes.

CSI's 300 g jar is taller, not wider

CSI's only in-stock listing with a 300 g fill is the Green Iridescent jar with bamboo lid - 300g: "Capacity - 300g Diameter - 7cm Height - 10cm". The white iridescent and borosilicate 300 g listings are out of stock on 29 September 2026. CSI's 150 g Clear Glass Jar with Golden Lid is also listed at about 7 cm outer diameter. So the step from 150 g to 300 g within CSI's range is a step in height at about the same width: row 1 of the table, not the wider jar of your plan. CSI lists no jar at 8, 8.5 or 9 cm; the next wider listing is the 10 cm Apothecary Glass Candle Jar with Dome Lid, sold as 500 g and 700 g.

There is a second reason to measure the Green Iridescent before trusting it. Its page does not say whether 7 cm is inside or outside. If it is outside, a 0.35 cm wall (our assumption) leaves about 6.3 cm inside: a 31.17 cm² pool, 12055% against a 7.0 cm inside jar, so your old wick would face less pool. And the listed figures only sit comfortably together if 7 cm is close to the inside: a 10 cm tall jar 6.3 cm inside holds about 311.7 ml to the brim (base ignored), roughly 281 g of wax at the 0.9 rule of thumb, under 300 g; at 7.0 cm inside it holds about 384.8 ml, roughly 346 g, which leaves about 1.34 cm of headspace above a 300 g fill. Weigh water to your fill line before you plan a 300 g candle in it, or ask us to confirm the inside diameter.

Bracketing the wider 300 g jar

Our worked example: your 200 g candle is 7.0 cm inside, Luxury Soy Wax CSI 464 at 8% Woody Oud (16 g oil + 184 g wax), approved on one Eco C2. The 300 g version goes in your own jar, 9.0 cm inside, at the same load (24 g + 276 g). Hold wax, oil, load, jar lot, fill line, pour temperature, cure and room constant. Vary one thing: the wick build.

The 3.5 cm spacing is our starting point for testing, not a recommendation: it is geometry that puts each flame 2.75 cm from the wall and 3.5 cm from its neighbour. Where to put two wicks before comparing sizes is the 9 cm two-wick placement post. Hold both tabs with a Steel Wick Holder if its line of holes fits your jar and your spacing (the page states no pitch), or with two sticks.

Six candles in grams, wicks and rupees

Per 300 g candle, before the jar: ₹258.23 on one C2, ₹260.79 on Cotton Braided, ₹260.59 on two C1s. The 200 g candle on C2 was ₹175.30. Oil (₹108.75) and wax (₹140.04) are almost the whole difference; the wick choice moves the cost by a few rupees, so choose it on the burn, not the price. Costs exclude labour, freight, packaging and GST.

What to buy, and what to skip

Five items, chosen on page statements, price and stock on 29 September 2026. CSI publishes no wick-performance data, so nothing is ranked on burn results. Candle counts in the oil table use 16 g (200 g) and 24 g (300 g) of oil per candle at 8%.

Frequently asked questions