How much fragrance oil do you need for a 50ml perfume?
A 50ml perfume at 25% needs 12.5ml (11.88g) of fragrance oil. Concentration tables for 30, 50 and 100ml bottles, the formula behind them, and why the gram figure never matches the millilitre one.
The short answer
In a 50ml bottle, 20% is 10ml, 25% is 12.5ml and 30% is 15ml of fragrance oil; the rest is base, either a ready-made solution or perfumer's alcohol. Measured on a scale those come to 9.5g, 11.88g and 14.25g, because fragrance oil has a density of about 0.95 g/ml, so the gram figure is always smaller than the millilitre one.
The formula
One line. Multiply the bottle volume by the concentration and divide by a hundred:
oil_ml = bottle_ml × concentration ⁄ 100 · base_ml = bottle_ml − oil_ml
For the weight, multiply the result by the density: grams = ml × density. The defaults are 0.95 g/ml for fragrance oil and 0.79 g/ml for a ready-made base; if your supplier gives you a different figure, use theirs.
50ml bottle: concentration table
| Concentration | Oil (ml) | Oil (g) | Base (ml) | Base (g) |
|---|---|---|---|---|
| 15% | 7.5 | 7.13 | 42.5 | 33.58 |
| 18% | 9 | 8.55 | 41 | 32.39 |
| 20% | 10 | 9.5 | 40 | 31.6 |
| 22% | 11 | 10.45 | 39 | 30.81 |
| 25% | 12.5 | 11.88 | 37.5 | 29.63 |
| 30% | 15 | 14.25 | 35 | 27.65 |
Other bottle sizes
As long as the concentration stays the same, the calculation scales directly with the bottle: a 100ml bottle takes exactly twice the oil of a 50ml one. The most common sizes at 25%:
| Bottle size | Oil (ml) | Oil (g) | Base (ml) |
|---|---|---|---|
| 10 ml | 2.5 | 2.38 | 7.5 |
| 15 ml | 3.75 | 3.56 | 11.25 |
| 30 ml | 7.5 | 7.13 | 22.5 |
| 50 ml | 12.5 | 11.88 | 37.5 |
| 100 ml | 25 | 23.75 | 75 |
Which concentration should you pick?
There is no single correct concentration. Home perfumers most often work between 18% and 30%: around 20% for everyday wear, 25-30% for something heavier and longer-lasting. But this is a safety decision as much as a stylistic one. If the IFRA limit of the oil you are using sits below that range, the limit is your ceiling. We go through how to choose in a separate article.
Should you measure in ml or grams?
Millilitres if you work with a syringe, grams if you work with a precision scale. What matters is not mixing the two inside one formula: the same 25% read by volume and by weight produces two different bottles. Professional perfumery works by weight as standard, and IFRA limits are defined by weight too. The numbers behind that difference are in volume or weight, and the full grams-to-ml table is here.
To run the numbers for your own bottle size and concentration:
Perfume calculatorStarting from the oil you already have
Plenty of people ask it the other way round: "I bought 50 grams of oil, how many bottles is that?" That is the reverse of this calculation and it has its own tool: how many bottles from your fragrance oil.