Dilution calculator how much stock and water to mix
Type your stock, the strength you want and how much you need. We work out the stock and water to measure, and what the chemical in it costs at the cheapest of 14 stores we compare.
- Measure out
- 100 millilitres
- of the 1 M stock
- Add water
- 900 millilitres
- to make 1 litre at 100 mM
- The chemical in it
- 5.84 grams
- of Sodium Chloride, worth $0.05 at the lowest price per gram we found
- See every price
Measure the stock, then add water up to the final amount and mix. For an acid, add the acid to the water, never water to the acid.
Common dilutions, worked out
- 10X to 1X, 1 litre
- 100 millilitres of stock and 900 millilitres of water
- 1 M to 100 mM, 1 litre
- 100 millilitres of stock and 900 millilitres of water
- 5 M to 150 mM, 500 millilitres
- 15 millilitres of stock and 485 millilitres of water
- 50% to 10%, 100 millilitres
- 20 millilitres of stock and 80 millilitres of water
- 1 M to 1 mM, 10 millilitres
- 10 microlitres of stock and 9.99 millilitres of water
- 100 mM to 10 mM, 50 millilitres
- 5 millilitres of stock and 45 millilitres of water
How to dilute a stock solution
- Work out the stock. Stock = target strength × final amount ÷ stock strength. The calculator above does it for you.
- Measure the stock. With a pipette or measuring cylinder.
- Add water up to the final amount. For an acid, put the water in first and add the acid to it, never the other way round.
- Mix. Swirl or invert until it is even.
What the words mean
- The formula
- C1 × V1 = C2 × V2: stock strength × stock amount = target strength × final amount
- X strength
- 10X is ten times the working strength. 10X to 1X is 1 part stock to 9 parts water
- Mixed units
- The stock and target can be in different units. Going between molar and percent uses the chemical's molar mass
More free tools
How it works: stock = target × final amount ÷ stock, with both strengths turned into grams per litre first (molar mass from PubChem). The chemical's cost is its grams at the lowest price per gram we found. Prices cover 3,967 chemicals: each store's in-stock pack price, in US dollars at European Central Bank rates of 2026-10-29, without shipping or tax.