Coffee Ratio Guide: 1:15 vs 1:16 vs 1:17
1:16 is the ratio to start at for filter coffee. That's 1 gram of coffee to 16 grams of water, so about 31g of coffee for a 500mL brew. It's strong enough to taste deliberate and forgiving enough to survive a slightly off grind.
Move to 1:15 if you want it heavier, 1:17 if you want it lighter and cleaner. That's the whole decision.
Use the Coffee Ratio Calculator to get coffee and water in grams for any ratio and any brew size.
Grams of coffee for common brew sizes
Water is measured in millilitres and coffee in grams, which works because 1mL of water weighs 1g.
| Water | 1:15 (stronger) | 1:16 (default) | 1:17 (lighter) |
|---|---|---|---|
| 250mL, one mug | 16.7g | 15.6g | 14.7g |
| 350mL, large mug | 23.3g | 21.9g | 20.6g |
| 500mL, two mugs | 33.3g | 31.3g | 29.4g |
| 750mL, small plunger | 50.0g | 46.9g | 44.1g |
| 1,000mL, large plunger | 66.7g | 62.5g | 58.8g |
| 1,500mL, batch brewer | 100.0g | 93.8g | 88.2g |
What the ratios actually taste like
| Ratio | Character | Best for |
|---|---|---|
| 1:14 | Heavy, syrupy, close to concentrate | Milk drinks, iced coffee where ice will dilute it |
| 1:15 | Strong and full bodied | Plunger, darker roasts, people who like it punchy |
| 1:16 | Balanced default | Pour over and filter, almost any bean |
| 1:17 | Lighter and cleaner, more clarity | Light roasts, single origins with fruit character |
| 1:18 | Tea-like, delicate | Very light roasts, big batch brewing |
Ratios by brew method
Ratio isn't universal. Immersion methods and espresso work on different numbers entirely.
| Method | Ratio | Contact time | Grind |
|---|---|---|---|
| Pour over (V60, Kalita) | 1:16 | 2:30 to 3:30 | Medium fine |
| Plunger / French press | 1:15 | 4 minutes | Coarse |
| AeroPress | 1:12 to 1:16 | 1:30 to 2:30 | Medium fine |
| Batch filter machine | 1:16 to 1:17 | Machine controlled | Medium |
| Moka pot | Fill basket level, water to the valve | Until it gurgles | Fine, not espresso fine |
| Cold brew concentrate | 1:8 | 12 to 18 hours | Coarse |
| Cold brew ready to drink | 1:15 | 12 to 18 hours | Coarse |
| Espresso | 1:2 (18g in, 36g out) | 25 to 32 seconds | Fine, dialled to the shot time |
The three things that matter more than the ratio
1. Grind size
Ratio sets strength. Grind sets extraction, which is what actually makes coffee taste good or bad.
- Bitter, harsh, dry finish: over-extracted. Grind coarser, or lower the water temperature, or shorten the brew.
- Sour, thin, salty, disappointing: under-extracted. Grind finer, or use hotter water, or brew longer.
People try to fix bitter coffee by using less coffee. That makes it weaker and still bitter. Fix the grind first, then adjust the ratio for strength.
2. Water temperature
Aim for 92°C to 96°C. Boiling water off a kettle is 100°C, which scalds lighter roasts. Wait 30 to 45 seconds after the kettle clicks and you're roughly in range.
3. Bean freshness
Coffee is best somewhere between 7 and 21 days after roast for filter, and often a little later for espresso. Supermarket bags with a best before date 12 months out and no roast date are usually months old. Local roasters print the roast date, which is the number worth reading.
Grind fresh. Pre-ground coffee loses most of what makes it interesting within about 15 minutes of grinding, and a $150 hand grinder beats a $1,500 machine fed stale grounds.
Stop using scoops
A level tablespoon of ground coffee is anywhere from 5g to 7g depending on grind size, bean density and roast level. Across a 500mL brew that's a swing of more than 20% in strength.
Kitchen scales that read to 1g cost about $15. Scales that read to 0.1g cost about $30 and are worth it if you make espresso. This is the cheapest improvement available to a home brewer.
Australian cup sizes, because they're not standard
- Metric cup (Australian recipes): 250mL
- US cup (most online recipes): 240mL
- Standard home mug: 300mL to 350mL
- Takeaway small: about 230mL. Regular: about 350mL. Large: about 450mL
- Plunger sizes are quoted in "cups" of about 125mL, so a 3-cup plunger is 350mL and an 8-cup is 1L
A plunger described as 8-cup does not hold 8 mugs of coffee. It holds three.
Troubleshooting
| Problem | Most likely cause | Fix |
|---|---|---|
| Bitter and drying | Over-extracted | Grind coarser, or drop water temperature to 92°C |
| Sour and thin | Under-extracted | Grind finer, or use hotter water, or brew longer |
| Weak but not sour | Ratio too high | Move from 1:17 towards 1:15 |
| Strong but muddy | Grind too fine for the method | Coarsen the grind, keep the ratio |
| Flat and boring | Stale beans or filtered-to-death water | Check the roast date, use ordinary tap or lightly filtered water |
| Pour over draining too slowly | Grind too fine or filter clogged | Coarsen the grind, rinse the filter first |
Related tools
- Coffee Ratio Calculator for coffee and water in grams
- Coffee Savings Calculator if you want to know what the daily flat white costs you
- Unit Converter for grams, millilitres, ounces and cups
Frequently asked questions
What is the best coffee to water ratio?
1:16 is the standard starting point for filter coffee, which is 15.6g of coffee for 250mL of water or 31g for 500mL. Move to 1:15 for a stronger cup and 1:17 for a lighter, cleaner one.
How much coffee do I need for 500mL of water?
About 31g at 1:16, 33g at 1:15 or 29g at 1:17. Since 1mL of water weighs 1g, you can weigh both on the same kitchen scales.
Why is my coffee bitter even though I used the right ratio?
Bitterness is almost always over-extraction, not too much coffee. Grind coarser, or drop the water temperature to around 92 degrees, or shorten the brew time. Reducing the dose makes it weak and still bitter.
What ratio should I use for a plunger?
1:15 with a four minute steep and a coarse grind. For a 1 litre plunger that is about 67g of coffee. Note that plunger sizes are quoted in 125mL cups, so an 8-cup plunger holds 1 litre, not 8 mugs.
Do I really need scales for coffee?
Yes, if you want consistency. A level tablespoon of ground coffee varies from 5g to 7g depending on grind and bean, which is a strength swing of more than 20% across a 500mL brew. Scales that read to 1g cost about $15.