For most filter coffee, start with a 1:16 coffee-to-water ratio: 1 g of dry coffee for every 16 g of brewing water. That means 20 g of coffee and 320 g of water. If you like a more concentrated cup, try 1:15. If you prefer it lighter, try 1:17. The best ratio is the one that makes a cup you want to brew again.
How we use ratios at the roastery
At the roastery, we usually brew with a Chemex. Same routine: weigh the coffee, grind it, heat the water. There are plenty of things that can change the cup, but one of the easiest to notice is how much water we use for the amount of coffee.
Want it a little stronger? Try 1:15. That's usually my go-to. You might love it, or you might prefer more water. There's no coffee police. The important thing is finding the ratio you enjoy and being able to repeat it. Because apparently “ehhh… that looks like enough water” isn't the most reliable brewing method. 😂
What does a 1:16 coffee-to-water ratio mean?
The ratio compares the weight of dry coffee to the weight of the water you use to brew it. At 1:16, multiply the grams of coffee by 16 to get the grams of water. A kitchen scale makes this much easier than counting scoops or watching the fill line on a kettle.
For a 20 g dose, here are three places to start:
| Coffee-to-water ratio | Dry coffee | Brewing water | What to try it for |
|---|---|---|---|
| 1:15 | 20 g | 300 g | A more concentrated cup; my usual Chemex starting point |
| 1:16 | 20 g | 320 g | A useful middle starting point |
| 1:17 | 20 g | 340 g | A lighter cup |
The water amounts above are water poured into the brewer, not the amount of finished coffee in your mug. Some water stays in the grounds and filter. You can weigh the water directly on your scale; for everyday brewing, its weight in grams is close to its volume in millilitres.
If your recipe calls for 30 g of coffee, the same math gives you 450 g of water at 1:15, 480 g at 1:16, or 510 g at 1:17. One number to remember, then a little multiplication.
How do I find the ratio I actually like?
Brew one cup at 1:16. For your next cup, use the same coffee, grind, brewer and technique, but change the water amount. With 20 g of coffee, moving to 300 g or 340 g of water gives you a comparison you can actually taste.
Write down what you actually liked: “More body at 1:15” or “I prefer this coffee at 1:17.” You don't need to turn breakfast into a cupping session. A note on your phone will do. If you want to take it further, try the same ratio with two different coffees. The measurements give each bag a fair comparison; the flavours are where things get interesting.
This week's coffee challenge: Weigh your coffee and water and see what ratio you're actually brewing. If you already do that, change just the ratio and taste the difference. If you brew espresso, compare two beverage yields instead; the filter-coffee numbers below don't transfer directly to a shot. Play with it. Curiosity, experimentation and a little trial and error are part of what makes coffee fun.
Does a stronger ratio mean more caffeine?
Using more coffee for the same amount of water generally means more caffeine in that serving, because you've used more coffee. But “stronger” can also mean more intense flavour or a more concentrated drink. A 1:15 ratio tells you how much coffee and water went into the brewer; it does not tell you the exact milligrams of caffeine in the mug. The beans and brewing conditions also matter.
My coffee tastes sour or bitter. Should I change the ratio?
Maybe, but first ask what you mean by “off.” If a cup tastes pleasantly balanced but thinner than you'd like, try a little less water. If it tastes too heavy, try more. Ratio affects concentration and can also change extraction, because changing the amount of water can change how long the water meets the grounds.
If the cup is noticeably sour, bitter or astringent, ratio may be only one piece of the puzzle. Grind size, brew time, pouring and water can all affect the result. Change one thing at a time so you can tell what helped. Our guide to grind size and flavour is a useful next stop if the ratio is consistent but the taste isn't.
Can I use 1:16 for French press, drip coffee or AeroPress?
It's a reasonable place to begin with filter and immersion brewers, including drip and French press. A Chemex, a French press and an AeroPress don't brew in exactly the same way, so expect to adjust the grind, technique and possibly the ratio for the method and the coffee. If you have a recipe you already love, keep it.
Espresso uses a different convention. A common espresso starting recipe uses 18 g of ground coffee to make 36 g of liquid espresso in the cup, called 1:2. That compares coffee with finished beverage, rather than coffee with the brewing water poured into a filter brewer. If you make espresso, follow an espresso recipe and adjust the yield to your taste.
Do different beans need different ratios?
They may taste best to you at different ratios. A change of coffee also brings changes in roast, processing and how the beans grind. Start with a repeatable recipe when you open a new bag; taste it before you adjust. A coffee that feels perfect at 1:15 in my Chemex might be the one you prefer at 1:16 in your brewer.
If you're choosing a bag to experiment with, browse our coffees and pick flavours you already know you enjoy. Then give that coffee a fair chance with a measured recipe.
Some mornings I want the familiar cup. Other mornings I want to see what happens if I change the recipe. That's the fun of knowing where I started: I can always find my way back.
From our family roastery to your mug,
Adriana