How to Use Our Brew Ratio Calculator (And Why Ratios Matter)

You've probably seen coffee recipes that say things like "use a 1:16 ratio" or "15g to 250ml" and thought: what does that actually mean? And how do I scale it for two cups instead of one?

That's exactly why we built the Brew Ratio Calculator. Pick your method, set your dose, choose how many cups — and it tells you exactly how much coffee and water you need. No mental math required.

But before you start plugging in numbers, it helps to understand why ratios matter in the first place.

What Is a Brew Ratio?

A brew ratio is the relationship between the weight of your coffee grounds and the weight of your water. It's written as 1:X, where X is how many grams of water you use per gram of coffee.

For example:

• 1:16 means 1 gram of coffee for every 16 grams of water
• 1:2 (espresso) means 1 gram in, 2 grams out
• 1:5 (cold brew concentrate) means a much stronger steep that you dilute later

The ratio determines the strength of your cup. A lower number (like 1:12) produces stronger coffee. A higher number (like 1:17) produces a lighter, more delicate cup.

The Standard Ratios

Every brew method has a sweet spot. Here's what our calculator uses as defaults — these are the ratios that produce a balanced cup for most people:

How to Use the Calculator

It takes about 10 seconds:

1. Pick your brew method. Tap one of the six options — espresso, pour over, French press, AeroPress, cold brew, or moka pot.
2. Set your dose. How many grams of coffee per cup? The default is 18g, which works great for most methods. Adjust if you like it stronger or lighter.
3. Choose your cups. Making coffee for two? Three? The calculator scales everything automatically.

That's it. You'll see your total coffee weight, water volume (in both ml and oz), plus the recommended temperature, grind size, and brew time for your method.

When to Adjust the Ratio

The default ratios work for most coffees, but you might want to adjust based on:

• Bean origin. Light, fruity Ethiopian beans often taste better at 1:17 (pour over) — a slightly lighter ratio lets the delicate flavors come through. Dark roasts can handle 1:15.
• Freshness. Older beans (past 3-4 weeks) lose intensity. You might want to dose slightly higher to compensate.
• Personal taste. There's no "correct" ratio — just starting points. If you consistently want it stronger, lower the ratio. If it feels heavy, raise it.

Going Deeper

Ratios are just one piece of the puzzle. If you want to understand how grind size, water temperature, and timing all work together, check out these guides:

• Pour Over Brewing Guide for Beginners — the full step-by-step process
• Espresso Grind Size Explained — how to dial in your shot
• French Press: The No-Nonsense Guide — the simplest way to brew great coffee
• Coffee Glossary — every term you'll encounter, explained simply