Coffee Calculator - Calculate Perfect Coffee to Water Ratio

Free coffee calculator to size your brew with accurate coffee-to-water ratios for strong, balanced, or mild coffee in a clean black & white layout.

Updated: November 2025 • Free Tool

Coffee Brew Ratio Calculator

Used only when "Custom ratio" is selected.

Optional: accounts for water absorbed by grounds.

Results

Recommended Coffee Dose
0 g
Total Brew Water 0 ml
Estimated Yield in Cups 0 cups
Ratio Used 1:0
Brew Style Summary -

What is a Coffee Calculator?

A Coffee Calculator is a free brewing tool that converts your target servings or water volume into precise coffee and water amounts using proven brew ratios. It removes guesswork so every batch tastes consistent instead of random.

This calculator is ideal when you want to:

  • Dial in daily brews so your morning coffee tastes the same every time.
  • Scale recipes for guests without over- or under-extracting your coffee.
  • Use beans efficiently by matching dose, volume, and desired cup strength precisely.

To convert kitchen units quickly for your coffee gear and recipes, check out our Cooking Measurement Converter to handle cups, tablespoons, ounces, and milliliters accurately.

For detailed ingredient weight conversions when pairing coffee with baked goods, use our Ingredient Volume-to-Weight Converter to get precise gram values for flour, sugar, and more.

To balance salt levels in savory coffee pairings or brunch dishes, try our Salt Conversion Calculator to convert accurately between table, kosher, and sea salt.

For planning pizza nights alongside coffee desserts, explore our Pizza Dough Calculator to scale dough recipes precisely by weight.

To correctly convert recipe cups when buying or measuring in bulk, use our Cups to Pounds Converter to match store packaging weights with your recipe plan.

How the Coffee Calculator Works

The calculator is based on the standard brew ratio formula:

Brew Ratio = Water (g or ml) ÷ Coffee (g)

For a target ratio 1 : R:

  • Coffee (g) = Water (ml) ÷ R
  • Water (ml) = Coffee (g) × R

When you choose cups, we convert using:

  • 1 cup brewed coffee = 6 fl oz ≈ 177 ml
  • Yield = Water in ml − Brew loss (absorption)

Ratios used: 1:15 strong, 1:16 balanced, 1:17 mild, or a custom 1:R you select.

Key Concepts Explained

Brew Ratio

The ratio of water to coffee grounds. Lower ratios (1:15) taste stronger; higher ratios (1:17) taste lighter. Keeping this stable is essential for repeatable flavor.

Extraction Consistency

Using grams for both coffee and water ensures even extraction across brews. Random scoops or cup estimates lead to sour, bitter, or flat coffee.

How to Use This Coffee Calculator

1

Choose Mode

Decide whether you know desired cups, total water, or coffee grams you plan to use.

2

Set Quantity

Enter number of cups, water volume, or coffee amount using realistic values.

3

Pick Strength

Select strong, balanced, mild, or custom and adjust the ratio if needed.

4

Brew Precisely

Use the recommended grams of coffee and water for clean, repeatable coffee.

Benefits of Using This Coffee Calculator

  • Consistent flavor: Lock in a repeatable recipe instead of guessing.
  • Bean efficiency: Avoid wasting specialty coffee with incorrect ratios.
  • Quick scaling: Instantly plan brews for one person or a full group.

Factors That Affect Your Coffee Results

Grind Size & Brew Time

Finer grinds extract faster and can taste bitter if paired with too long a brew; coarse grinds may taste weak if under-extracted. Keep ratio fixed while tuning grind and time.

Bean Freshness & Roast

Lighter roasts and very fresh beans may benefit from slightly stronger ratios. Dark roasts can feel intense even at milder ratios. Use the calculator as a baseline, then tweak to taste.

Coffee Calculator - Free online tool to calculate ideal coffee-to-water ratios for consistent, barista-quality brews with instant results
Professional coffee calculator interface showing precise coffee-to-water ratios, grams-based dosing, and compact black and white layout for consistent brewing results.

Frequently Asked Questions (FAQ)

Q: How does this coffee calculator work?

A: It applies a coffee-to-water ratio (for example, 1:16) to your chosen number of cups, water volume, or coffee dose, then returns precise grams for both coffee and water.

Q: Which brew methods is this calculator best for?

A: It is optimized for drip, pour-over, French press, and similar filter brews. Espresso and cold brew use different ratios and are not directly covered here.

Q: Can I adjust the strength to match my taste?

A: Yes. Choose strong, balanced, or mild presets, or set your own custom ratio to fine-tune extraction based on your beans and preferences.

Q: Why are milliliters used instead of ounces only?

A: Milliliters align directly with grams, making ratios simple, accurate, and easy to reproduce for any brew size.

Q: Do I need a scale to use this calculator?

A: For best results, yes. A small digital scale gives accurate doses. Without a scale, values are still helpful, but less consistent because scoops vary.

Q: Does brew loss significantly change the results?

A: Yes. Coffee grounds and filters retain some water. Including a realistic loss value ensures your final brewed volume matches how many cups you actually want to pour.