The Ultimate Coffee-to-Water Ratio Guide
The single most important variable in brewing great coffee — and most people get it wrong. Here's your complete visual reference.
Why Ratio Matters More Than Anything Else
You can buy the best beans on earth, grind them perfectly, and use water at exactly 94°C — but if your ratio is off, the cup won't taste right. The coffee-to-water ratio is the foundation that every other variable builds on.
Too much coffee and you get an intense, harsh, over-extracted brew. Too little and you're drinking flavoured water. The ratio determines strength (how concentrated the cup is) and directly influences extraction (how much flavour you pull from the grounds).
The Specialty Coffee Association recommends a ratio of 1:15 to 1:18 for most filter methods. That's 1 gram of coffee for every 15–18 grams of water. But different methods have very different sweet spots.
The Golden Ratio by Brew Method
Here's a visual reference for the most popular brewing methods. These are starting points — your taste preference, bean origin, and roast level will all shift the ideal ratio.
How to Calculate Your Dose
Once you know your target ratio, the math is simple. Decide how much coffee you want to brew, then work backwards.
Adjusting for Taste
The ratios above are starting points. Here's how to adjust based on what you're tasting:
Too Sour / Thin?
Your coffee is under-extracted. The water didn't pull enough flavour from the grounds.
Too Bitter / Harsh?
Your coffee is over-extracted. Too much flavour was pulled, including unpleasant compounds.
Common Mistakes
After helping thousands of people brew better coffee, these are the ratio mistakes we see most often:
- Measuring coffee by volume instead of weight. A "scoop" can vary by 30% depending on grind size and how you scoop. Use a scale — even a cheap kitchen scale will transform your consistency.
- Not accounting for water retained in grounds. Pour-over methods absorb roughly 2x the coffee weight in water. So 15g of coffee absorbs ~30ml. If you pour 225ml, your cup will contain about 195ml.
- Using the same ratio for all roast levels. Darker roasts are more soluble and extract faster. If you use a 1:15 ratio for a dark roast the same way you would for a light roast, you'll likely over-extract. Try 1:16 or 1:17 for dark roasts.
- Ignoring water quality. The ratio assumes your water is good. If your tap water tastes off, no ratio will save the brew. Filtered water with a TDS of 75–150 ppm is ideal.
Quick Reference Cards
Bookmark these for your morning brew: