Coffee Calculator
Free Coffee Calculator for tea & coffee recipes. Enter amounts to convert, scale, or adjust ingredients precisely. Includes formulas and worked examples.
Formula
Coffee (g) = Water (ml) ÷ Ratio | Water (ml) = Coffee (g) × Ratio
The coffee-to-water ratio determines brew strength. The standard 'golden ratio' is 1:16 (1g coffee per 16ml water). Different brewing methods use different ratios: espresso uses 1:2, cold brew uses 1:5, and drip/pour-over uses 1:15 to 1:17. This calculator adjusts automatically based on your chosen method.
Worked Examples
Example 1: Morning Pour Over for Two
Problem: Calculate the coffee and water needed to brew 2 cups (480 ml) of pour-over coffee using a 1:16 ratio.
Solution: Water needed: 2 cups × 240 ml = 480 ml\nCoffee needed: 480 ml ÷ 16 = 30 g\nTablespoons: 30 g ÷ 5 = 6 tbsp\nEstimated caffeine: 30 g × 10 mg/g = 300 mg total (150 mg each)\nBrew time: 3-4 minutes\nWater temperature: 96°C / 205°F\nGrind: Medium-Fine
Result: 30g coffee | 480ml water | 1:16 ratio | ~300mg caffeine total
Example 2: Cold Brew Concentrate Batch
Problem: Make a cold brew concentrate using 100g of coarsely ground coffee at a 1:5 ratio.
Solution: Coffee: 100g (extra coarse grind)\nWater: 100g × 5 = 500 ml\nRatio: 1:5 (concentrate)\nSteep time: 12-24 hours at room temperature\nYield after filtering: ~400 ml concentrate\nTo serve: dilute 1:1 with water or milk\nDiluted servings: ~3-4 cups\nCaffeine per diluted cup: ~250 mg
Result: 100g coffee | 500ml water | 1:5 ratio | Steep 12-24 hrs
Frequently Asked Questions
What is the golden ratio for coffee to water?
The golden ratio for coffee brewing is generally considered to be 1:16, meaning one gram of coffee for every 16 grams (or milliliters) of water. This ratio was established by the Specialty Coffee Association (SCA) as part of their brewing standards, aiming for an extraction yield of 18-22% and a total dissolved solids (TDS) of 1.15-1.35%. However, taste is subjective, so many coffee enthusiasts adjust this ratio to suit their personal preference. A stronger cup might use 1:14 or 1:15, while a lighter brew could go up to 1:17 or 1:18. The key is consistency — once you find your preferred ratio, sticking with it produces reliable results every time.
How much coffee do I need per cup?
A standard cup of coffee (8 oz / 240 ml) typically requires about 15 grams of ground coffee when using the golden ratio of 1:16. That translates to roughly 2 level tablespoons of ground coffee. However, a 'cup' can vary widely: a standard US measuring cup is 8 oz, but many coffee makers define a 'cup' as only 5-6 oz. A typical mug holds 10-12 oz. So for a 12 oz mug, you would need about 22-23 grams of coffee. For espresso, you use a much more concentrated ratio of about 1:2, meaning around 18-20 grams of coffee for a double shot of roughly 36-40 ml. Always weigh your coffee with a scale for the best consistency.
How does water temperature affect coffee brewing?
Water temperature significantly impacts extraction. The SCA recommends 92-96°C (197-205°F) for most hot brewing methods. Water that is too hot (above 96°C) causes over-extraction, pulling out bitter compounds and harsh tannins from the coffee grounds. Water that is too cool (below 90°C) leads to under-extraction, producing a sour, thin, and acidic cup. Dark roasts often benefit from slightly lower temperatures (90-93°C) since they are more soluble, while light roasts may need the higher end (94-96°C) to fully extract their complex flavors. Cold brew bypasses this entirely by using room temperature or cold water with a much longer steeping time of 12-24 hours to achieve a smooth, low-acidity concentrate.
How much caffeine is in a cup of coffee?
An average 8 oz (240 ml) cup of brewed coffee contains approximately 80-100 mg of caffeine, but this varies widely based on several factors. The coffee bean variety matters: Robusta beans contain nearly twice the caffeine of Arabica beans (about 2.2% vs 1.2% by weight). Brewing method also plays a role — espresso has about 63 mg per 1 oz shot, but since it is served in small quantities the total per serving is lower than drip coffee. A 12 oz drip coffee can contain 120-150 mg. Cold brew concentrate can have 150-200 mg per 8 oz due to the long extraction time. Light roasts actually contain slightly more caffeine than dark roasts because roasting burns off some caffeine. The FDA recommends a daily limit of 400 mg for most healthy adults.
Can I use Coffee Calculator on a mobile device?
Yes. All calculators on NovaCalculator are fully responsive and work on smartphones, tablets, and desktops. The layout adapts automatically to your screen size.
How do I get the most accurate result?
Enter values as precisely as possible using the correct units for each field. Check that you have selected the right unit (e.g. kilograms vs pounds, meters vs feet) before calculating. Rounding inputs early can reduce output precision.