Fragrance Calculator

1. Choose Formula to split a recipe written in percents, or Dilution to reach a target strength.
2. Enter the batch size and pick grams, milliliters or ounces. In Formula mode, type each ingredient and its percent; the balance ingredient fills whatever is left.
3. Read each amount in the results and the table under them. Copy or Save the report for your notebook.

A fragrance calculator converts a scent formula from percents into real amounts to weigh or measure. Perfumers write formulas in percents so a recipe can be scaled from a 10 mL test to a litre without changing its balance.

It suits people blending perfume, body mist, room spray, beard oil or diffuser blends at home. The ingredients are usually fragrance oils, essential oils (plant extracts, which the FDA notes have no regulatory definition), absolutes, and a carrier such as perfumer alcohol or a plant oil.

This page covers perfume-style formulas and dilutions. Candle wax loads are handled by the candle wax calculator, and soap batches need the soap lye calculator, because both depend on their base material as well as the scent.

Every amount is a simple share of the batch. The dilution mode also allows for materials that are already diluted.

1. Add up the listed percents. Anything under 100% goes to the balance ingredient; anything over 100% is flagged.
2. Multiply each percent, as a decimal, by the batch size.
3. For a dilution, divide the target strength by the strength of what you add. A 10% pre-dilution must be added at 10 times the amount of a neat oil.

Weight Percent vs Volume Percent

OpenStax Chemistry defines mass percentage as the mass of a component over the mass of the whole, and volume percentage as volume over volume. They give different numbers for the same mix. NIST SP 811 says to state which one you mean: a mass fraction or a volume fraction. The calculator treats grams and ounces as weight percent and mL as volume percent. Ethanol has a density of 0.789 g/mL, so 35 mL of ethanol weighs about 27.62 g.

Formula: a 50 mL perfume at 70% ethanol, 20% rose oil and 10% vanilla absolute. Ethanol = 0.70 x 50 = 35 mL, rose oil = 0.20 x 50 = 10 mL, vanilla absolute = 0.10 x 50 = 5 mL. The total is 100%, so there is no balance.

Formula with a balance: a 100 g blend with 8% bergamot oil, 5% lavender oil and 4% cedarwood oil. Those make 17 g, and the other 83 g is perfumer alcohol.

Dilution: 30 mL at 15% strength from a neat oil needs 30 x 15 / 100 = 4.5 mL of oil and 25.5 mL of carrier. As ethanol, that carrier weighs about 20.12 g. With 10 mL of oil you could make up to 66.67 mL at the same strength.

Pre-dilution: 20 g at 2% using a 10% pre-diluted material needs 20 x 2 / 10 = 4 g of the pre-dilution and 16 g of carrier.

The math is fixed, but a few choices change the numbers you should enter.

Weight or Volume

Oils and alcohol have different densities, so 10% by weight is not 10% by volume. Pick one basis for the whole formula. Weighing in grams on a small scale is the most repeatable.

Pre-diluted Materials

Many strong materials are sold or kept as 1% or 10% dilutions. Enter the material strength so the calculator adds the right amount.

Batch Size and Scale Resolution

Tiny batches produce amounts below what a kitchen scale can read. Scale the batch up, or use a jeweller scale that reads 0.01 g.

Product Type and Ingredient Limits

IFRA, the International Fragrance Association, publishes Standards that restrict, set specifications for or prohibit specific fragrance ingredients. Limits depend on the ingredient and how the product is used, so this tool does not suggest a strength. Check each material against the IFRA Standards Library and your supplier's documents.

The two modes answer different questions, and mixing them up is a common source of error.

Names such as eau de parfum and eau de toilette describe strength, but no single binding definition sets their percentages, and brands use them differently. Record your own percent instead of a label name.

Scaling a Test Blend

Write a 10 mL test in percents, then scale the same formula to 100 mL without changing the balance.

Converting a Recipe to Your Units

Turn a gram recipe into ounces, or check weights with the ounces to grams converter.

Planning a Dilution

Work out how much oil and carrier to buy for a batch at a fixed strength.

Keeping Records

Copy the report into a notebook so a good blend can be repeated exactly.

1. Mixing Weight and Volume

Measuring oils in mL and alcohol in grams in the same formula breaks the percents.

2. Percents That Pass 100%

The ingredients of one batch cannot add up to more than 100%. The tool flags it.

3. Treating a Pre-dilution as Neat Oil

A 10% dilution delivers one tenth of the material. Enter its strength.

4. Using Percent of Carrier Instead of Percent of Total

15 mL of oil added to 100 mL of alcohol is 13.04% of the total, not 15%. This tool always uses percent of the whole batch.

5. Assuming a Strength Is Safe Because a Calculator Produced It

The tool only does arithmetic. Safety depends on each ingredient and the product use.

The arithmetic is exact; amounts are shown to 2 decimal places. The limits are about materials, not math.

Multiply the batch size by the percent as a decimal. 20% of a 50 mL batch is 0.20 x 50 = 10 mL.

Multiply the batch by 0.15. A 30 mL bottle needs 4.5 mL of neat oil and 25.5 mL of alcohol or carrier.

Weight is more repeatable, because oils and alcohol have different densities. Use one basis for the whole formula.

Enter 10 as the material strength. The calculator adds 10 times as much as it would for a neat oil.

The rest goes to the balance ingredient, often perfumer alcohol or a carrier oil. The tool shows its amount.

There is no single number. The IFRA Standards set limits for specific ingredients that depend on how a product is used, so check each material.

It does the percent math, but candle and soap loads depend on the wax or oils. The candle wax and soap lye calculators handle those.

Ethanol weighs about 0.789 g per mL, so 1 mL is roughly 0.79 g. Other carriers differ.

For retail cosmetics sold in the U.S., fragrance ingredients can be listed simply as "Fragrance", according to the FDA.

No. The math runs in your browser and nothing is sent to us. Save keeps a result only in this browser.

• IFRA Standards and fragrance safety (International Fragrance Association; the Standards set limits, restrictions and prohibitions for specific ingredients).
• Fragrances in cosmetics (U.S. Food and Drug Administration; essential oils have no regulatory definition; "Fragrance" labeling).
• Mass percentage and volume percentage (OpenStax Chemistry 2e, section 3.4; ethanol density 0.789 g/mL).
• Mass fraction vs volume fraction (NIST Special Publication 811, section 7.10.2).