Coffee Ratio Calculator
Coffee grams for any water amount at 1:15, 1:16, or 1:17.
What it does
Brew ratios weigh coffee against water so cups repeat. A 1:16 ratio means one gram of grounds for every sixteen grams of water, the balanced middle of the classic drip and pour over band from mild 1:17 to strong 1:15.
The tool above takes the water amount in grams, milliliters, liters, ounces, or cups with the strength choice. It returns coffee grams, an approximate tablespoon count, and the ratio label.
The default brews 600 g of water at 1:16: 37.5 g of coffee, about 3.8 tablespoons at 10 g each. Two big mugs of 300 g need the same 37.5 g total, since water sets coffee directly.
The band follows National Coffee Association brew guidance with Specialty Coffee Association golden cup standards behind the 1:15 to 1:17 middle. Both advise weighing over scooping because grind and roast move spoon weight substantially.
How to use
- Enter the water you will brew with.
- Pick its unit; milliliters and grams match one to one.
- Pick mild, balanced, or strong.
- Weigh the coffee grams first for the real accuracy.
- Use tablespoons only when no scale is near.
Formula
- ratio
- 15, 16, or 17 parts water per one part coffee.
- 10 g
- Rough grams per tablespoon of ground coffee.
- ml = g
- Water converts one to one by volume.
Spoon math assumes medium ground coffee near 10 g per tablespoon; fine grinds pack heavier and light roasts weigh more per scoop. Grams stay exact regardless.
Worked example
Example: 600 g water at 1:16
Water 600 g, strength balanced 1:16.
- Water: 600 g needs no conversion.
- Coffee: 600 / 16 = 37.5 g.
- Spoons: 37.5 / 10 = 3.8 tbsp.
- Ratio label reads 1:16.
- Tool shows 37.5 g, 3.8 tbsp, 1:16.
Reference table
| Strength | Coffee | Spoons |
|---|---|---|
| 1:17 mild | 35.3 g | 3.5 tbsp |
| 1:16 balanced | 37.5 g | 3.8 tbsp |
| 1:15 strong | 40.0 g | 4.0 tbsp |
Limits
- Drip and pour over band only; espresso runs near 1:2.
- Spoon counts are rough by grind and roast.
- Taste beats math: adjust one step after the first brew.
- Caffeine per cup follows dose and extraction, not ratio alone.
Common mistakes
- Scooping light roast fine grounds like medium scoops.
- Reading 1:16 backwards as sixteen coffees to one water.
- Using fluid ounces as weight ounces for coffee.
- Changing grind and ratio at once when dialing in.
- Brewing by cup lines without checking milliliters.
Try it yourself
Quick checks. Answers sit tucked under each question.
500 ml at 1:17?
500 / 17 = 29.4 g, about 2.9 tbsp.
1 L at 1:15?
1000 / 15 = 66.7 g.
2 cups (473 g) at 1:16?
473 / 16 = 29.6 g.
Questions
What is a good coffee ratio?
1:16 balanced for drip and pour over, 1:17 milder, 1:15 stronger.
How much coffee for 600 g water?
37.5 g at 1:16, about 3.8 tablespoons.
ml or grams for water?
Either. Water weighs one gram per milliliter, so the numbers match.
Why weigh instead of scoop?
Grind size and roast shift spoon weight by a fifth; grams never move.
What about espresso?
Far tighter, near 1:2 coffee to yield by weight, outside this page.
How many tablespoons per gram?
About 10 g per tablespoon of medium ground coffee, used here for the rough count.