Coffee-to-Water Ratio Calculator
Eyeballing coffee measurements is the easiest way to end up with an inconsistent brew from one day to the next. Enter how many cups you're making, your mug size, and your preferred strength below to get an exact grams figure.
Work out your coffee-to-water ratio
Enter how many cups you're brewing, your mug size, and your preferred strength.
A balanced, everyday cup
For 960ml of water, use:
64.0g of ground coffee
That's roughly 16.0g per cup at a 1:15 ratio.
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- Single or couple households
- 1.1L
Currently unavailable
Pros
- Automatic pod recognition adjusts brew size and strength
- Compact footprint suits smaller kitchens
- Makes both espresso and larger mug-sized coffee
Cons
- Locked into Nespresso Vertuo pod range
- Family cooking
- 1.8L
£319.99
Pros
- Grinds fresh beans for every cup
- One-touch cappuccino and latte macchiato functions
- Adjustable grinder and milk froth settings
Cons
- Requires regular descaling and cleaning cycles
- Larger footprint than a pod machine
- Family cooking
- 1L (8 Cups)
£46.00
Pros
- Heat-resistant borosilicate glass carafe with polished stainless steel frame
- Simple manual brewing with no pods or electricity needed
- Dishwasher safe and easy to disassemble for cleaning
Cons
- Glass carafe can chip or crack if knocked
- Grounds settle at the bottom, needs a coarse grind to avoid sediment
Frequently asked questions
What is a good coffee-to-water ratio to start with?
A ratio of around 1:15 (1 gram of coffee per 15ml of water) is a widely used starting point for a balanced, everyday cup. From there, adjust up toward 1:17 for a milder brew or down toward 1:13 for something stronger.
Does the ratio change for different brewing methods?
The core ratio works as a general guide across most methods, but some — like espresso, which uses far less water relative to coffee — follow a very different ratio entirely. This calculator suits filter, cafetière/French press, and pour-over style brewing.
Should I weigh coffee or use a scoop?
Weighing gives a far more consistent result than scooping, since ground coffee density varies with grind size and bean type — a heaped scoop of fine grounds weighs noticeably more than the same scoop of coarse grounds.
Why does my coffee taste bitter even at the right ratio?
Bitterness is often more about over-extraction (water in contact with grounds for too long, or too fine a grind) than the ratio itself. If your ratio is right but the taste is still bitter, try a slightly coarser grind or a shorter brew time first.
How this calculator works
The calculator uses a standard recommendation of 1 gram of ground coffee per 170ml (approximately 6 fl oz) of water as a starting point – a ratio often used for a medium strength brew. You input the number of cups you want to make and select your desired strength, which affects the amount of coffee used per cup. The calculator then automatically calculates the total amount of ground coffee needed based on this ratio, providing a precise measurement in grams.
Coffee Grind Size & Water Temperature – Key Factors for UK Brewing
- **Grind Size Matters:** A finer grind generally extracts more flavour, particularly with darker roasts common in the UK. Using a burr grinder is highly recommended for consistent particle size and better extraction; blade grinders can create uneven results.
- **Water Temperature:** Aim for around 93-96°C (200-205°F) – this is hotter than boiling water, which can scorch the coffee grounds and lead to bitterness. Let boiled water sit for about a minute before pouring over your grounds.
- **Water Quality:** Tap water in the UK is generally fine, but filtered water will consistently yield better results. Hardness levels can affect extraction; consider using distilled water if you have very hard tap water.
- **Coffee Bean Roast:** Lighter roasts often benefit from a slightly coarser grind than darker roasts, which tend to be more soluble. Experiment to find your preferred balance.
- **Brew Method:** The calculator assumes a pour-over or drip method where the grounds are fully saturated with hot water. French press brewing requires different considerations due to longer contact times.
Worked example: Brewing for 4 People
Let's say you’re making a pot of coffee for four people, and you want a medium strength brew. You select ‘4 cups’ and ‘Medium’ on the calculator. The calculator instantly displays a total ground coffee requirement of approximately 80 grams (give or take, depending on your bean density). This equates to roughly £3 - £5 for a standard 250g bag of medium-roast beans from Fortnum & Mason or Booths – a solid starting point.
To use this result, weigh out 80 grams of ground coffee and add it to your brewing device. Ensure you’re using freshly roasted beans for the best flavour profile. Remember that these figures are just a guide; personal taste preferences can vary greatly.
More questions answered
What if I want a stronger brew?
Increase the amount of coffee used per cup. You could add an extra 10-20 grams to the calculation, depending on your preference. Experiment with different bean types – darker roasts generally produce stronger flavours.
What if I’m using a different cup size?
Simply adjust the number of cups entered into the calculator. The ratio remains consistent at 1g per 170ml, so changing the cup count will automatically recalculate the total amount of coffee needed.
Does this calculator account for bean density?
The calculator provides an approximation based on standard bean densities. However, bean density can vary significantly depending on roast level and origin. For more precise results, consider weighing your beans before use.
What if I’m using a French press?
French press brewing involves longer contact times with the grounds, requiring a coarser grind than pour-over methods. Experiment with adjusting the grind size to control extraction and avoid over-extraction – resulting in bitterness.
Can I use this calculator for espresso?
While you can input the number of shots you want, this calculator is primarily designed for larger volume brewing methods like drip or pour-over. Espresso requires a significantly different process and ratios.
How accurate is this calculation?
The accuracy depends on factors like grind consistency, water temperature control and your personal preference. It's a starting point – fine-tune the results based on how you taste your coffee.
What if I’m using instant coffee?
This calculator isn't designed for instant coffee, which uses pre-dissolved granules. You would need to adjust the amount of instant coffee powder according to its package instructions – typically 1-2 teaspoons per cup.
Is it possible to convert grams to ounces?
Yes, the calculator automatically converts the result to approximately US fluid ounces (fl oz) for convenience. However, remember that conversions can slightly vary depending on the density of your coffee grounds.
What’s the best way to store my ground coffee?
Store your ground coffee in an airtight container away from heat, light and moisture. A dark, cool pantry is ideal. Avoid storing beans whole for longer periods – grind just before brewing for maximum freshness.
Can I use this calculator with decaffeinated coffee?
Yes, you can absolutely use this calculator with decaffeinated coffee! The ratio remains the same; however, some decaf coffees may require a slightly finer grind to achieve optimal extraction – experiment to find what works best for your chosen blend.