Ratio Calculator
Pick your brew method, enter coffee or water, and get the perfect ratio. All calculations happen in your browser.
Coffee to water ratio calculator
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Common Coffee Ratios
| Brew Method | Ratio | Coffee (g) | Water (ml) | Best For |
|---|---|---|---|---|
| Pour Over (V60, Chemex) | 1:15 | 15g | 225ml | Clean, bright cups |
| French Press | 1:14 | 15g | 210ml | Full-bodied, rich coffee |
| AeroPress | 1:14 | 15g | 210ml | Versatile, quick brewing |
| Espresso | 1:2 | 18g | 36g yield | Concentrated shots |
| Cold Brew Concentrate | 1:5 | 100g | 500ml | Dilute before drinking |
| Cold Brew (ready to drink) | 1:12 | 50g | 600ml | Smooth, ready to enjoy |
How Coffee Ratios Work
A coffee ratio like "1:15" means 1 gram of coffee to 15 grams of water. Since 1 millilitre of water weighs almost exactly 1 gram, you can treat grams and millilitres interchangeably for water. So 15g of coffee at a 1:15 ratio needs 225ml of water.
Ratios matter more than volume measurements like "scoops" or "cups" because coffee beans vary in density. A tablespoon of a light roast weighs differently than a dark roast. Weighing with a scale removes the guesswork and gives you a repeatable cup every time. If you want to learn more, check out our post on understanding coffee ratios.
To adjust strength: a lower second number means stronger coffee (1:13 is stronger than 1:15), and a higher number means lighter (1:17 is lighter than 1:15). The Specialty Coffee Association (SCA) recommends 1:15 to 1:18 for drip and filter methods. Most people land somewhere around 1:15 to 1:16 as their go-to. For specific guidance, browse our brew guides - they include recommended ratios for each method, including V60 and more.
Frequently Asked Questions
What is the best coffee to water ratio?
It depends on the brew method. For pour over, 1:15 is a reliable starting point. French press works well at 1:14. Espresso is typically 1:2. Use the calculator above to dial in the exact grams for any ratio.
How many grams of coffee per cup?
For a standard 250ml cup of filter coffee at a 1:15 ratio, use about 16.7g of coffee - roughly 3 level tablespoons. For a larger 350ml mug, you will need around 23g.
What does a 1:15 coffee ratio mean?
For every 1 gram of coffee, use 15 grams (or millilitres) of water. So 15g of coffee needs 225ml of water, and 20g of coffee needs 300ml.
How do I make stronger coffee?
Use a lower ratio like 1:13 or 1:12 instead of 1:15. You can also grind finer or extend the brew time, but changing the ratio is the most direct way to control strength.
Is the coffee ratio by weight or volume?
Always by weight. A kitchen scale is the most reliable way to measure both coffee and water. 1ml of water weighs approximately 1 gram, so you can measure water by volume if needed.
What ratio does Starbucks use?
Most commercial drip machines, including those at Starbucks, use around 1:17 to 1:18. This produces a lighter cup compared to the 1:15 that many specialty coffee drinkers prefer.