Use quick presets, or set a custom target ratio. The form adapts to your chosen mode and stays readable on mobile.
| Method | Target Ratio | Coffee | Water | Bloom (12%) | Estimated Yield* |
|---|---|---|---|---|---|
| Pour-over | 16.5:1 | 20 g | 330 ml | 40 ml | 290 ml |
| Drip / Batch | 17.0:1 | 30 g | 510 ml | 61 ml | 450 ml |
| French press | 15.5:1 | 25 g | 388 ml | 47 ml | 338 ml |
| AeroPress | 15.0:1 | 18 g | 270 ml | 32 ml | 234 ml |
| Cold brew | 8.0:1 | 60 g | 480 ml | 58 ml | 360 ml |
*Yield uses absorption 2.0 ml/g as a simple estimate.
- Brew ratio: ratio = water ÷ coffee (water and coffee in base units).
- Water from coffee: water = coffee × ratio.
- Coffee from water: coffee = water ÷ ratio.
- Bloom water: bloom = water × (bloom% ÷ 100).
- Yield estimate: yield = water − (coffee × absorption).
- Pick a calculation mode based on what you know.
- Choose a brew method, or enter a custom ratio.
- Enter coffee or water amounts with your preferred units.
- Adjust bloom and absorption for better yield estimates.
- Press Calculate to see results above the form.
- Use Download CSV or Download PDF for your garden log.
Why brew ratios matter outdoors
A brew ratio expresses how much water is used for each gram of coffee. In practical terms, it controls strength and extraction balance when you brew between watering cycles. A tighter ratio like 14–15:1 produces a heavier cup, while 17–18:1 tastes lighter and can highlight acidity. Consistency is the main advantage: repeating the same ratio makes grind and time changes easier to evaluate.
Method presets and typical ranges
Different brewers favor different ranges. Pour-over often lands near 16–17:1 for clarity, drip batches near 17:1 for a clean daily mug, and French press around 15–16:1 for body. Cold brew concentrates commonly run 6–10:1 because dilution happens later. Espresso is usually discussed as beverage yield to coffee mass, often 1.5–2.5:1, rather than kettle water.
Bloom, degassing, and flow control
Blooming wets the grounds and releases trapped gases, improving water contact. Many brewers start with 8–15% of total water, then add the remaining water in steady pours. If bloom is too low, channeling and uneven extraction can increase. If bloom is too high, the slurry cools and slows, affecting total contact time.
Yield estimates and absorption
Beverage yield is usually lower than the poured water because coffee holds liquid. A simple estimate is retained water ≈ coffee grams × absorption factor. Paper filters commonly retain around 1.8–2.2 ml per gram, while metal filters can retain slightly less. Tracking yield helps you plan cup size, especially when brewing multiple servings during garden tasks.
Field notes for repeatable results
Use the note field to record grinder setting, water temperature, and brew time. When taste shifts, adjust one variable at a time: change ratio first for strength, grind for extraction, and time for refinement. Exporting CSV or PDF makes it easy to keep a simple brew log alongside planting notes.
1) What ratio is a safe starting point for most coffees?
Start at 16:1 using 16 ml water per gram of coffee. Adjust toward 15:1 for stronger cups or 17:1 for lighter cups after tasting one or two brews.
2) Should I match coffee grams to water milliliters?
For most brewing, 1 ml of water is close to 1 gram, so ratios work cleanly. Measure coffee by mass for best consistency, and measure water by volume or mass.
3) Why does my cup taste weak even at a tight ratio?
Weak flavor can come from under-extraction. Try a finer grind, slightly longer brew time, or a hotter pour. Keep ratio the same so you can isolate the improvement.
4) How accurate is the yield estimate?
It is a planning estimate based on absorption. Real yield changes with filter type, grind, and agitation. Use your measured cup output once, then tune the absorption factor to match.
5) What bloom percentage should I use?
A common range is 8–15% of total water. Fresh coffee may benefit from a slightly higher bloom. If the bed drains too fast, reduce agitation and keep bloom steady.
6) Can I use this for multiple cups?
Yes. Enter your total target water or total coffee for the batch, and the calculator scales everything, including bloom and yield. Keep grind and pour rate appropriate for larger brews.