Coffee Ratio Calculator
Work out how much ground coffee a given volume of water needs at your preferred brew ratio.
The golden ratio and where it comes from
The Specialty Coffee Association's guideline is about 1:16 to 1:18 by weight for filter brewing, which is where the 'golden ratio' phrase originates. Espresso runs far tighter at 1:2. Ratio controls strength; grind size and time control extraction, and confusing the two is why adding more coffee to a bitter brew makes it worse.
What this page needs from you
This page asks for water in ml and brew ratio in :1. From those it returns coffee needed in g, together with water per gram, tablespoons (approx.), stronger at 1:14 and weaker at 1:18. Every figure updates as you type, and nothing you enter leaves your browser.
Rounding, and when it matters
Nothing is rounded internally; only the display is. That keeps the arithmetic exact and means the figures agree with a spreadsheet, but it also means a result shown to two decimals may carry more precision than the inputs deserve. If you measured something to the nearest whole unit, do not read meaning into the digits after the point.
When to use something else
Every calculation is a model, and a model is a deliberate simplification. Where the answer will drive a decision that is expensive or hard to reverse, use this to understand the shape of the problem and then confirm the specifics with someone who can see details this page cannot.
The formula
Coffee (g) = water (ml) ÷ ratio
Every result on this page comes from this formula. Nothing is rounded until the final display, so figures match a spreadsheet to the cent.
How to use the Coffee Ratio Calculator
- Fill in each field with your own figures — the defaults are only there as an example.
- The result updates as you type, so there is no button to press.
- Check the breakdown under the main result for the supporting numbers.
- Use the copy button to take the result with you, or share the link to reload the same inputs.
Coffee Ratio Calculator — frequently asked questions
Is this coffee ratio calculator free to use?
Yes. Every calculator on the site is free, needs no sign-up, and runs entirely in your browser, so your figures never leave your device.
How accurate is the result?
The maths is exact for the formula shown on the page. Accuracy in the real world depends on your inputs and on assumptions the formula cannot see, so treat the output as a well-grounded estimate rather than a quote.
Can I use it on my phone?
Yes. The page is responsive, weighs a few kilobytes and works offline once loaded, so it behaves the same on a phone as on a desktop.
What people search for
This page answers each of these searches. They are the exact phrases visitors use to find the coffee ratio calculator.
- coffee ratio calculator
- golden ratio coffee
- brew ratio calculator
- how much coffee per cup
- coffee to water ratio
About this calculator
Written and reviewed by The Samsung Calculator editorial team. Every calculator is written against a published formula, reviewed against at least one independent reference implementation, and dated when it changes.
Last reviewed September 10, 2026 · Calculation runs client-side · No data collected · Report an error