How Much Reed Diffuser Base and Fragrance Oil Do I Need to Make 10 Bottles of 100 ml Each for a Small Business?

The numbers, before the reasoning

The net calculation is the easy part. CSI's base pages state fragrance load as a share of the total blend, so ten 100 g fills at 20% are 1,000 g of blend: 200 g of oil and 800 g of base. That assumes your blend weighs 1.00 g per ml — an example, because no density is published for any CSI base or oil; at ±5% ten 100 ml fills weigh 950 g to 1,050 g. The rest of this page is about the gap between that net number and an order that does not leave you one bottle short on bottling day; the method for making each bottle is in the 100 ml method pillar, and whether 20% suits your oil is the subject of the load pillar.

Order of operations matters. Count whole extra bottles first (the reference bottle), then fixed samples, then apply the percentage loss to the subtotal — once, not twice — and round up to real packs last. If you apply the loss to the net figure only, you under-cover the reference bottle; if you apply it to the rounded packs, you are adding allowance to liquid you have not mixed. Calculating 100 bottles of 120 ml with density and filling losses runs the same method at production scale, and density and the number of 100 ml bottles from 1 kg deals with the conversion in depth.

The mistake that buys 20% too much base

The most common error in diffuser batch maths is to treat the bottle size as the base quantity and add oil on top: "100 ml of base plus 20% oil per bottle". For ten bottles that is 1,000 ml of base and 200 ml of oil — 1,200 ml of blend, enough for 12 bottles, not ten. Worse, the oil is 20 parts in 120, so the true load is 16.67%, not 20%. You over-buy base, under-dose fragrance, and the label no longer matches the formula.

Rounding to real CSI packs

CSI lists its diffuser bases only as 500 ml (and Pure Performance also as 100 g); there is no 1 kg, 5 kg or 25 kg listing, and larger quantities are quoted on WhatsApp with no published volume discount. The example uses Lift Base because its page names fruity families — apple, mango, peach — alongside floral, citrus and green, and Orchard Pear is a fruity oil. The base need of 923.7 g is grams; the bottle is millilitres, so whether two bottles are enough depends on density, which is not published:

Two bottles (1,000 ml) cover the need at any base density of 0.924 g/ml or more. Weigh 100 ml of the base in a beaker on arrival: if it is lighter than that, the second bottle will not quite stretch, and you either drop the reference bottle or buy a third. For the oil, every in-stock Orchard Pear size was considered and the cheapest combination covering 230.9 g is 2 × 100 g + 1 × 50 g for ₹1,000.00, leaving 19.1 g. Orchard Pear's 500 g pack is ₹1,870.00 and its 1 kg ₹3,738.00 — ₹3.74 and ₹3.74 per gram against ₹3.80 in 100 g — so for a ten-bottle batch the larger packs only buy stock you do not yet need.

Two lines deserve a comment. Bottles: ten for sale plus one reference bottle is 11, and bottles come in packs of ten, so the eleventh bottle costs you a second pack — 9 bottles carry over to your next batch. If you decide not to keep a reference bottle, one pack covers the batch exactly, with no spare for a breakage. Reeds: 88 reeds are needed; 1 × pack of 100 at ₹800.00 is cheaper than 50 + 25 + 25. The leftovers — about 76 g of base and 19.1 g of oil — are not enough for another 100 ml bottle at 20% (it needs 20 g of oil); keep them for a clarity re-check or a small 50 ml test.

Buy it all now, or pilot first?

If you have already made this exact formula and it passed its clarity hold, buy the whole order. If you have not, split it. Stage one is everything you need to make and check the reference bottle: one 500 ml of base, a small oil pack, and the bottles and reeds (which you need for the batch anyway). Mix 113.4 g at 20% — 22.7 g of oil — rest it 24–48 hours, and check the clarity sample at 48 hours and 7 days. Only when it passes do you buy stage two and mix the ten.

Staging costs ₹75.06 more than buying everything at once, because the pilot's oil is bought as its own small pack instead of being part of the cheapest combination for the whole batch; the pilot oil still ends up in the batch. What it buys you is the right to stop: if Orchard Pear hazes in Lift at 20%, you have spent ₹4,233.04, not ₹6,122.00, and the bottles and reeds are still usable with a different oil or base. Checking a 20% formula for compatibility and the mixing method are the two pages to read before mixing the pilot.

Mixing and bottling the ten as one batch

Once the pilot has passed, the ten bottles are made from one batch of 1,041.2 g — the gross blend minus what the pilot already used. One batch means one weighing of oil, one weighing of base, one rest period and one clarity sample that speaks for every bottle. Ten small blends mean ten chances to misread the scale. The 250 ml silicone beaker is too small for a batch this size; mix in any clean, dry, clear glass or stainless vessel that holds about 1.5 litres (not a CSI item), or split the batch into two identical halves, each weighed separately and recorded.

Reeds go in when the bottle reaches its customer or its display shelf — not on bottling day. A capped bottle without reeds loses nothing; a reeded bottle starts emptying the moment the first reed is wet. Pack the 8 reeds per bottle separately, and put the instruction to flip them once after the first hour (the Pure Performance page's guidance — check what your own base's page says) on your label or card. Your reference bottle is the exception: reed it on bottling day, flip it, weigh it, and start its schedule on day 0.

What each of the ten bottles costs

Two answers, both honest. What this order costs per bottle sold: ₹6,122.00 ÷ 10 = ₹612.20, of which the liquid is ₹319.80. That figure carries the reference bottle, the samples, the filling loss and every leftover — it is your real cash cost for this batch. What a bottle costs once you are in production: with Orchard Pear at the 1 kg rate (₹3.74/g), Lift at an example 1.00 g/ml, the ₹106.20 bottle and 8 black reeds at ₹8.00:

At ±5% density the base line moves between ₹167.47 and ₹185.09. The gap between ₹612.20 (this batch) and ₹420.80 (production) is mostly leftovers and the reference bottle, not price: per-gram oil prices on CSI's catalogue rarely fall much above 100 g, so scale lowers your cost per bottle mainly by using up what you buy. What a 100 ml diffuser costs to make adds labels, box and labour, and base for 100 bottles at 20% scales this calculation tenfold.

The decision rule

Mix the ten as one batch, not ten separate small blends: one batch means one load, one rest period and one clarity sample that speaks for every bottle. If your beaker is too small, scaling a trial formula without changing the ratios shows how to split a batch without drifting. And if ten becomes fifty for a corporate client, fifty diffusers for corporate gifting is the next step.

The CSI products in this order

Frequently asked questions