A good cup of coffee starts before the grinder: it starts with how much coffee you use for how much water. The Coffee Brewing Ratio Calculator below does that math for pour over, French press, Chemex, AeroPress, and automatic drip brewers, so you can scale a recipe up or down without guessing.
Pick your method, enter either the coffee you have or the water you want to use, and adjust the ratio until it matches your taste. Everything runs in your browser, so there is nothing to sign up for.
Your Brewing Recipe
- Brewing Method
- Pour Over / V60
- Coffee
- 20 g
- Water
- 320 ml
- Water (US fl oz)
- Ratio
- 1:16
- Strength
- Balanced
What is a coffee brewing ratio?
A brewing ratio compares the weight of ground coffee to the amount of water. A ratio of 1:16 means 1 gram of coffee for every 16 grams (roughly 16 milliliters) of water. Because the first number is always 1, a lower second number means more coffee relative to water, so the brew is more concentrated. A higher number means less coffee and a lighter brew.
Weighing is more consistent than measuring with scoops, because the same scoop can hold noticeably different amounts of coffee depending on roast level, grind size, and how it is packed. A small kitchen scale that reads to 1 g, or ideally 0.1 g, is enough for everyday brewing.
Published guidance varies. The Specialty Coffee Association’s often-cited reference point is about 55 grams of coffee per liter of water (roughly 1:18), while many home brewers settle somewhere between 1:15 and 1:17. There is no single correct ratio; the right one is the one that tastes good to you with your coffee and your equipment.
How to use the calculator
- Choose your brewing method. The calculator loads a starting ratio for it.
- Choose what you already know: your coffee amount or your water amount.
- Enter the amount. The recipe updates as you type.
- Fine-tune the ratio with the number box, the slider, or the Stronger, Balanced, and Milder buttons.
- Optionally show water in US fluid ounces, then use Copy results to paste the recipe into your notes.
The calculator treats 1 gram of water as 1 milliliter. Hot water is slightly less dense, so a milliliter weighs a little under a gram, but for home brewing the difference is small.
Starting ratios by brewing method
| Method | Starting ratio | Stronger | Milder | Notes |
|---|---|---|---|---|
| Pour Over / V60 | 1:16 | 1:15 | 1:17 | Clean, bright cups. Grind size and pouring pattern matter as much as the ratio. |
| French Press | 1:15 | 1:14 | 1:16 | Full-immersion brew with a fuller body. Use a coarse grind. |
| Chemex | 1:16 | 1:15 | 1:17 | The thick paper filter gives a very clean cup. |
| AeroPress | 1:15 | 1:13 | 1:17 | Recipes vary widely, from concentrated to full-strength; treat 1:15 as a middle starting point. |
| Automatic Drip Coffee Maker | 1:16 | 1:15 | 1:17 | The machine controls water flow and temperature, so ratio and grind are your main levers. |
Practical ratio examples
| Method | Coffee | Water | Ratio |
|---|---|---|---|
| Pour Over / V60 | 20 g | 320 ml | 1:16 |
| French Press | 30 g | 450 ml | 1:15 |
| Chemex | 42 g | 672 ml | 1:16 |
| AeroPress | 15 g | 225 ml | 1:15 |
| Automatic Drip | 60 g | 960 ml | 1:16 |
The finished cup weighs less than the water you poured, because ground coffee absorbs part of it (commonly about twice its own weight). If you want a specific cup size, pour somewhat more water than the volume of the cup.
How the ratio changes your coffee
Changing the ratio changes how concentrated the coffee is. For 300 ml of water, 1:16 uses 18.75 g of coffee and 1:15 uses 20 g, which is about 7 percent more coffee and a noticeably stronger cup.
Strength is not the same as extraction. Strength describes how much coffee is dissolved in the cup, while extraction describes how much of the coffee dissolved and what it tasted like on the way. As a rule of thumb, adjust the ratio when the cup is simply too strong or too weak, and look at grind size, water temperature, or brew time when it tastes sour, bitter, or flat.
Common brewing mistakes
- Measuring by volume (scoops or tablespoons) instead of weight.
- Changing several variables at once, so you cannot tell which change helped.
- Using the same ratio for every method. Immersion and drip brewers behave differently.
- Skipping grind adjustments. A ratio that works with one grind can taste weak or harsh with another.
- Forgetting that grounds absorb water, so the finished coffee weighs less than the water poured.
- Brewing with stale beans or old grounds; see our guide to storing coffee beans at home.
Frequently asked questions
What is the best coffee-to-water ratio?
There is no single best ratio. Many home brewers start between 1:15 and 1:17 for hot methods and then adjust toward a stronger or milder cup. Use the Stronger, Balanced, and Milder presets as starting points.
How do I use tablespoons instead of grams?
Weighing is more reliable, because a tablespoon of ground coffee can vary noticeably with roast and grind. As a rough approximation, a level tablespoon holds about 5 grams, but check it against a scale if consistency matters to you.
Can I measure water in cups?
Yes. One US cup is about 237 ml (8 US fluid ounces). Tick the fluid ounces option in the calculator to see the water amount in US fluid ounces as well.
Why does AeroPress start at 1:15 when recipes use other ratios?
AeroPress recipes range from concentrated brews that are diluted afterwards to full-strength cups. 1:15 is a middle starting point, and the Stronger and Milder presets move it toward 1:13 or 1:17.
Does this calculator work for espresso or cold brew?
It is designed for hot, filter-style and immersion brewing. For espresso, use the Espresso Extraction Calculator. For cold brew, see our guide to making cold brew at home.
Related guides on JoinWorky
- A coffee-to-water ratio guide for everyday brewing methods – the background behind the presets
- How to adjust coffee strength without making it harsh – what to change when the cup is too strong or too weak
- How to brew coffee for one – scaling a recipe down to a single cup
- How to brew pour-over coffee with a simple, repeatable routine – a step-by-step V60 routine
- French press coffee: grounds, water, and plunging – immersion brewing basics
- Coffee grind size explained – how grind changes the taste at the same ratio
More coffee tools
- Espresso Extraction Calculator – turn dose, yield, and time into a brew ratio.
- Coffee Brewing Temperature Guide – find a starting water temperature by method and roast.
- All JoinWorky coffee tools – the full directory.
About these recommendations
The starting ratios are drawn from widely published brewing guidance and common community recipes rather than a single authority. They are meant to be a sensible place to begin, not a guarantee of any particular flavor. Beans, grinders, water, and personal taste all change what works best.