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Dilution Ratio Calculator

This dilution ratio calculator turns a concentrate-to-diluent ratio like 1:8 into exact amounts. Enter the two parts of your ratio, tell it which volume you already know — the total you want to make, the concentrate you have, or the diluent you have — and type that amount. The other two amounts fill in instantly. It works with any unit you type (ml, oz, gallons, litres, drops) because the math itself never depends on units — you just add a label for the display.

What Is a Dilution Ratio?

A dilution ratio expresses how much concentrate to mix with how much diluent, written as two numbers like 1:8 or 1:32. The first number is the concentrate's share of the ratio, the second is the diluent's share, and together they describe the total "parts" that make up the finished mix — a 1:8 ratio is 9 total parts (1 concentrate + 8 diluent). What is a 1 to 5 dilution, for example? It's 1 part concentrate to 5 parts diluent — 6 total parts, so the concentrate makes up 1/6 of the final volume. The ratio itself never changes with scale: 1:8 describes the same mix whether you're making 90 ml or 90 litres.

How to Calculate a Dilution Ratio

The calculator mirrors how you'd actually work it out by hand. First, add the two ratio parts together to get the total parts. Then, depending on which amount you already know:

You know the total amount you want to make — each of concentrate and diluent is the total multiplied by its share of the total parts.
You know how much concentrate you have — diluent is the concentrate scaled up by the ratio (diluent parts ÷ concentrate parts), and total is the sum.
You know how much diluent you have — concentrate is the diluent scaled down the same way, and total is the sum.

Select the matching pill under "I know the" — Total amount, Concentrate, or Diluent — type that one number into Known amount, and both other figures update as you type. There's nothing to submit and nothing uploaded; it recalculates on every keystroke, right on your device.

Common Dilution Ratios by Use Case

A dilution ratio calculator gets used for many kinds of concentrate. Whatever you are mixing, use the ratio printed on the product's own label or instructions — strength varies by formulation, and the calculator only does the arithmetic:

Car detailing — all-purpose cleaners, wheel cleaners, and foam shampoos ship as concentrates with their own printed dilution ratio chart, ranging from roughly 1:4 for heavy-duty jobs to 1:20 or weaker for light maintenance.
Darkroom chemistry — film developer and stop bath are mixed from concentrates at the ratio given in their instructions.
Hydroponics — nutrient concentrates are diluted into a reservoir at the ratio on the nutrient label.
Drinks — cordials, syrups and coffee or tea concentrates are scaled to taste.

Whatever the concentrate, the steps are the same: enter the ratio, say which amount you already know, and read off the other two.

Dilution Ratio Chart Reference

For a quick reference, here's how much concentrate a few common ratios need to make 1 litre (1,000 ml) of total solution. Use the calculator above for any ratio or volume not listed — including gallons, ounces, or any other unit.

Ratio	Concentrate share	Concentrate per 1 L total
1:4	20%	200 ml
1:8	11.1%	111 ml
1:10	9.1%	91 ml
1:16	5.9%	59 ml
1:20	4.8%	48 ml
1:32	3.0%	30 ml
1:40	2.4%	24 ml
1:64	1.5%	15 ml
1:128	0.8%	8 ml
1:256	0.4%	4 ml

Frequently Asked Questions

How do you calculate a dilution ratio?

Add the two parts of the ratio together to get the total parts, then divide whichever amount you know by its share of that total. For a 1:8 ratio (9 total parts) making 900 ml, concentrate is 900 × (1/9) = 100 ml and diluent is 900 × (8/9) = 800 ml. This calculator does that division for you — enter the ratio and one known amount and it solves the other two instantly.

What does a dilution ratio like 1:5 actually mean?

A 1:5 dilution ratio means 1 part concentrate to 5 parts diluent — 6 total parts, so the concentrate makes up 1/6 (about 16.7%) of the final mix. It does not mean "5 times weaker" in a simple sense; it means for every unit of concentrate you use, you add 5 units of diluent alongside it, not instead of it.

What dilution ratio do detailers use for car-cleaning chemicals?

Detailing chemicals like all-purpose cleaners, wheel cleaners, and snow foam are typically sold as concentrates with a printed dilution ratio chart, commonly ranging from about 1:4 for heavy-duty use down to 1:20 or more for light maintenance washes. Check your product's own chart for the ratio, then set "I know the" to whichever amount you're starting from — a full spray bottle or a set amount of concentrate — to get the rest instantly.

Zep Professional Spray Bottles (32 oz, 3-pack)
Chemical-resistant bottles for the mix you just worked out.
McKillans Wide-Mouth Foam Cannon
Car shampoo at 1:10? This turns it into thick snow foam.
PetraTools EZ1 Battery Sprayer (1 gallon)
Mix a gallon of garden concentrate and spray it without pumping.

Helps keep the tools free. ✨

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