French Press Calculator
Enter your French press volume and preferred strength to get the exact coffee dose in grams, the precise ratio, and complete brew guidance — in real time.
French Press Calculator
How to Brew French Press (Step by Step)
- Preheat your French press. Pour a small amount of hot water into the carafe, swirl, and discard. This prevents the cold glass from dropping your brew temperature by several degrees during extraction.
- Grind coarse and weigh your coffee. Use the dose shown by this calculator. Grind to a coarse consistency — similar to coarse sea salt. Fine grinds slip through the metal mesh and produce muddy, bitter coffee.
- Add coffee and start your timer. Pour the grounds into the preheated carafe. Start your timer as soon as you begin adding water. Pour all the water at once (at 195–200°F / 90–93°C) to ensure even saturation.
- Stir at 1 minute. At the 1-minute mark, gently stir the grounds to ensure every particle is fully saturated and extracting. Place the lid on (plunger up) without pressing.
- Press and pour at 4 minutes. At 4 minutes, press the plunger slowly and steadily over about 20–30 seconds. Pour all the brewed coffee into a separate vessel or cups immediately — leaving it on the grounds causes over-extraction and bitterness.
Understanding the French Press Ratio
French press is a full-immersion brew method — the coffee grounds remain in contact with the water for the entire brew time, unlike pour over where water flows through the grounds and drains continuously. This immersion extraction is more efficient per unit of time than percolation, meaning French press tends to extract more flavour at a given ratio than pour over.
The standard French press coffee to water ratio is 1:15, which sits slightly stronger than the SCA's 1:18 recommendation because the metal mesh filter allows more oils and fine particles into the cup, adding body and richness. The ratio range of 1:12 to 1:17 covers most palates — 1:12 is very strong and full-bodied, while 1:17 is mild and clean. As you use this coffee to water ratio calculator, note that French press ratios are calibrated specifically for the method's immersion characteristics.
Because French press uses a coarse grind with relatively slow extraction, brew time has a larger effect on flavour than in faster methods. Steep for less than 3 minutes and you'll get under-extracted, sour coffee. Exceed 5 minutes and the additional extraction pulls harsh bitter compounds — especially noticeable with darker roasts. Four minutes at 1:15 is the most reliable starting point for any grind and origin.
French Press Ratio Reference Chart
| Carafe Volume | Mild (1:17) | Balanced (1:15) | Strong (1:13) | Bold (1:12) |
|---|---|---|---|---|
| 350ml (1 cup) | 20.6g | 23.3g | 26.9g | 29.2g |
| 500ml | 29.4g | 33.3g | 38.5g | 41.7g |
| 750ml | 44.1g | 50g | 57.7g | 62.5g |
| 1000ml (4 cup) | 58.8g | 66.7g | 76.9g | 83.3g |
| 1500ml (8 cup) | 88.2g | 100g | 115.4g | 125g |
Pro Tips for Better French Press Coffee
- Use a coarser grind than you think you need. Most home grinders set to "coarse" still produce too many fine particles for French press. Aim for a grind where the particles look like coarse sea salt — individual grains clearly visible. If your cup is consistently muddy or bitter, go even coarser.
- Let your water cool briefly after boiling. Water at 100°C (212°F) is too hot for French press and will scorch the grounds, producing harsh bitterness. Let it sit for 30–45 seconds off the heat to reach 90–93°C (195–200°F). A kettle thermometer eliminates guesswork.
- Pour all the coffee out immediately after pressing. This is the most commonly ignored step. Coffee left in the French press continues to extract through the grounds even after the plunger is down. Decant everything into a thermal carafe or cups right away.
- Clean the filter screen thoroughly. Coffee oils accumulate in the mesh and become rancid over time, introducing off-flavours that no amount of ratio adjustment can fix. Disassemble the plunger after every use and rinse all parts thoroughly.
- Try a shorter steep for lighter roasts. Light roasts extract faster and at lower temperatures than dark roasts. If you're using a light or single-origin coffee, try 3:30–4:00 minutes rather than the full 5 minutes to avoid over-extraction and preserve delicate fruity notes.
Frequently Asked Questions
The most versatile French press ratio is 1:15 — 1 gram of coffee for every 15ml of water. For a 350ml press, that's 23g of coffee. This ratio produces a well-balanced, full-bodied cup. If you prefer lighter coffee, try 1:17. For something bolder, 1:12–1:13 works well. Use this calculator to dial in your exact dose for any brew size.
Four minutes is the standard starting point. For a stronger brew, extend to 5 minutes, but never go beyond this — the additional extraction predominantly adds bitterness rather than flavour. For a milder cup, try 3:30 minutes. Brew time interacts with grind size: a coarser grind may need the full 5 minutes; a medium-coarse grind is often ready at 3:30–4:00.
Muddy or gritty French press is almost always caused by a grind that's too fine. Fine particles pass through the metal mesh filter and end up in the cup. Switch to a coarser grind — one where you can see individual particles clearly. If the problem persists, your mesh may be worn or damaged and need replacing.
French presses are typically labelled by cup count, but manufacturers use small 4 oz cups — so a "4-cup" French press holds about 500ml (enough for 2 standard mugs). A "8-cup" or 34 oz press (about 1 litre) is the most versatile size for 2–4 people. Whatever size you choose, always fill it within 2cm of the top for proper immersion.
French press coffee contains more cafestol and kahweol — diterpenes in coffee oils — than filtered coffee because the metal mesh doesn't remove them like a paper filter does. These compounds have been shown to raise LDL cholesterol with regular consumption. For most healthy adults, moderate French press consumption (1–2 cups daily) is unlikely to cause concern, but those managing cholesterol may want to switch to a paper-filtered method.
You can, but most pre-ground coffee sold for "drip" is too fine for French press and will produce a muddy, over-extracted result. If using pre-ground, look for coffee labelled "French press" or "coarse grind." Reduce your steep time to 3 minutes to partially compensate for the finer grind. For the best French press coffee, grinding fresh just before brewing makes a dramatic difference.