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Coffee Ratio Calculator

Perfect coffee brewing ratios for every method

Coffee Ratio Calculator: Perfect Coffee Brewing Ratios

Table of Contents - Coffee Ratio

How to Use This Calculator - Coffee Ratio

Select your brew method from the dropdown: Drip Coffee, Espresso, French Press, Pour Over, Cold Brew, or AeroPress. Each method has a recommended ratio that produces optimal results.

Choose your calculation direction: "Coffee Amount → Water Needed" if you know how much coffee you have, or "Water Amount → Coffee Needed" if you know how much coffee you want to brew.

Enter the known quantity—either coffee in grams or water in milliliters.

Click "Calculate" to see results. The output displays:

  • The complementary measurement (water needed or coffee needed)
  • The ratio used (e.g., 1:15)
  • Equivalent measurements in cups, ounces, and tablespoons
  • The expected strength (Light, Medium, Strong)
  • Brew method name and typical characteristics

The Core Principle: Coffee-to-Water Ratio

Coffee brewing is fundamentally about extraction—dissolving soluble compounds from ground coffee into water. The ratio of coffee to water determines strength (concentration) and affects extraction (what percentage of solubles actually dissolve).

Ratios are expressed as coffee:water. A 1:15 ratio means 1 gram of coffee for every 15 grams (or milliliters) of water. Higher ratios (1:17, 1:18) produce lighter coffee; lower ratios (1:12, 1:10) produce stronger coffee.

The Specialty Coffee Association recommends 55 grams of coffee per liter of water (approximately 1:18) as the "Golden Cup" standard. This produces a balanced cup where acidity, sweetness, and bitterness are in harmony.

Different brew methods call for different ratios because of varying extraction dynamics. Immersion methods (French press) extract differently than percolation methods (pour over). Espresso uses extreme ratios (1:2) because the concentrated output is meant for dilution or as a flavor base.

How to Calculate Coffee Ratios Manually

Basic formula: Water (g) = Coffee (g) × Ratio

Example: Pour over at 1:16 with 30g coffee Water = 30 × 16 = 480g (480ml)

Reverse calculation: Coffee (g) = Water (g) ÷ Ratio

Example: French press at 1:15 with 600ml water Coffee = 600 ÷ 15 = 40g

Recommended ratios by method:

  • Drip coffee: 1:15 to 1:17
  • Pour over: 1:15 to 1:17
  • French press: 1:12 to 1:15
  • AeroPress: 1:14 to 1:16 (standard); 1:6 for concentrated
  • Espresso: 1:1.5 to 1:2.5 (yield ratio, not brewing ratio)
  • Cold brew concentrate: 1:5 to 1:8

Tablespoon conversions:

  • 1 tablespoon ground coffee ≈ 6 grams
  • To convert: Grams ÷ 6 = Tablespoons

Cup conversions:

  • 1 cup of water = 240ml (8 fl oz)
  • A "cup" of brewed coffee is typically 5-6 oz in coffee maker terms

Real-World Applications

Consistency across batches. Using the same ratio every time produces consistent results. No more guessing how many scoops to use—weigh once, replicate forever.

Scaling for groups. Need coffee for 8 people instead of 2? Multiply everything proportionally. At 1:15 with 20g per serving: 160g coffee, 2,400ml water.

Troubleshooting weak or strong coffee. Too weak? Increase coffee (lower ratio like 1:14). Too strong? Decrease coffee (higher ratio like 1:17). Adjust by 10% increments.

Adapting recipes. A recipe says "2 tablespoons per 6 oz cup." Convert to grams: 12g coffee, 180ml water = 1:15 ratio. Now you can scale precisely.

Comparing brew methods. Understanding ratios reveals why French press tastes different from pour over, even with the same beans. Ratio differences compound with extraction differences.

Scenarios People Actually Run Into

The scoop inconsistency. You've been using "two scoops" but cups vary wildly. One morning it's perfect; the next it's weak. A scale and gram measurements eliminate this variation.

The concentrate confusion. Cold brew concentrate at 1:5 isn't meant to drink straight—it's diluted 1:1 or more with water or milk. AeroPress concentrated recipes similarly need dilution.

The pour over bloom dilemma. You weigh 30g coffee but recipes say "bloom with twice the coffee weight." That's 60g water for the bloom, subtracted from your total—so 480g total water means 60g bloom plus 420g remaining.

The espresso ratio mystery. Espresso ratios work differently. A 1:2 ratio means 18g coffee in, 36g liquid out. This isn't a brewing ratio like drip coffee; it's a yield ratio describing output.

The altitude adjustment. At high altitude, water boils at lower temperatures, potentially under-extracting coffee. You might need finer grind or slightly lower ratio to compensate.

Trade-Offs and Decisions People Underestimate

Strength versus extraction. More coffee (lower ratio) makes stronger coffee but can lead to under-extraction if water can't dissolve enough solubles. Less coffee (higher ratio) is lighter but can over-extract, becoming bitter.

Grind size interaction. Ratio and grind size work together. Finer grinds extract faster; coarser grinds slower. Changing ratio without adjusting grind may produce unbalanced results.

Water quality impact. Water is 98%+ of brewed coffee. Chlorinated tap water, very soft water, or very hard water all affect extraction. Ratio perfection means nothing with bad water.

Freshness of beans. Stale beans require different parameters. You might increase coffee (lower ratio) to compensate for faded flavors, but this masks the real problem.

Time versus ratio. In immersion brewing, longer steeping extracts more. A 1:15 French press steeped 4 minutes differs from the same ratio steeped 8 minutes. Ratio is one variable among several.

Common Mistakes and How to Recover

Measuring by volume, not weight. A tablespoon of finely ground coffee weighs more than the same tablespoon of coarsely ground coffee. Weight is the only reliable measure for consistency.

Using coffee maker "cup" markings. Coffee maker cups are typically 5 oz, not 8 oz. A "12-cup" coffee maker actually makes about 60 oz (7.5 actual cups). Measure water in milliliters.

Ignoring water retained in grounds. Grounds absorb water—roughly 2g water per 1g coffee. If you use 30g coffee, about 60g water stays in the grounds. Account for this when targeting final yield.

Changing multiple variables. Adjusted ratio, grind, and brew time simultaneously? You won't know which change affected the result. Change one variable at a time.

Using boiling water. 100°C water can over-extract and scald coffee. Optimal brewing temperature is 90-96°C (195-205°F). Let water cool 30-60 seconds after boiling.

Related Topics

Extraction yield. The percentage of coffee mass that dissolves into water. Target is 18-22%. Under-extracted coffee tastes sour; over-extracted tastes bitter.

Total dissolved solids (TDS). Measures coffee strength as dissolved solids concentration. 1.15-1.35% TDS is standard; espresso runs 8-12%.

Water chemistry. Ideal brewing water has moderate hardness (50-175 ppm), slightly alkaline pH, and no chlorine. Too soft under-extracts; too hard over-extracts.

Grind size. Finer grinds = more surface area = faster extraction. Espresso uses very fine (powder-like); French press uses very coarse (sea salt-like).

Bloom phase. Pre-wetting grounds releases CO₂ (from fresh beans) and prepares for even extraction. Standard bloom: 2× coffee weight in water, 30-45 seconds.

How This Calculator Works

The calculator stores recommended ratios for each brew method:

  • Drip: 1:15
  • Espresso: 1:2 (yield ratio)
  • French press: 1:12
  • Pour over: 1:16
  • Cold brew: 1:8
  • AeroPress: 1:14

Coffee-to-water calculation: Water (ml) = Coffee (g) × Ratio

Water-to-coffee calculation: Coffee (g) = Water (ml) ÷ Ratio

Unit conversions:

  • Water to ounces: ml ÷ 29.5735
  • Water to cups: ml ÷ 240
  • Coffee to ounces: g ÷ 28.35
  • Coffee to tablespoons: g ÷ 6 (approximate)

Strength classification: Based on ratio ranges—lower ratios (1:12 or less) are "Strong," middle ratios (1:13-1:16) are "Medium," higher ratios (1:17+) are "Light."

All calculations happen locally in your browser.

FAQs

What ratio should I start with?

For most methods, 1:15 or 1:16 is a good starting point. This produces balanced coffee. Adjust from there based on taste preference.

Why use grams instead of scoops?

Scoop volumes are inconsistent—grind size, how tightly packed, and scoop shape all vary. Weight is the only reliable, repeatable measurement.

What's the difference between pour over and drip ratios?

Similar ratios, but pour over offers more control. Drip machines have fixed parameters; pour over lets you adjust pour rate, bloom time, and water temperature.

How do I make stronger coffee without more caffeine?

Use a lower ratio (more coffee). Caffeine extraction maxes out quickly; a 1:12 ratio extracts similar caffeine to 1:16 but tastes much stronger.

Should I use the same ratio for dark and light roasts?

Light roasts are denser and may need slightly lower ratios (more coffee). Dark roasts are less dense and more soluble—slightly higher ratios can prevent over-extraction.

Why does my pour over taste different each time?

Likely inconsistent technique: pour rate, water temperature, total brew time, or grind size variation. Control these variables along with ratio for consistency.

How do I calculate for a specific cup size?

Measure your cup in milliliters. Divide by your target ratio. Example: 350ml mug at 1:15 = 23g coffee.

Is there such a thing as too much coffee in the ratio?

Yes. Below 1:10, water can't adequately extract; you get concentrated but under-extracted (sour, weak) coffee. Extraction physics limit how low ratio can go.

What's the difference between brew ratio and dose?

Dose is the amount of coffee used (in grams). Ratio is the relationship between coffee and water. You can use a 1:16 ratio with a 15g dose (240ml water) or a 30g dose (480ml water)—same ratio, different doses for different serving sizes.

How does water temperature affect extraction?

Hotter water extracts more quickly and aggressively. Too hot (above 96°C) can over-extract, causing bitterness. Too cool (below 90°C) under-extracts, causing sourness. The ideal range is 90-96°C (195-205°F) for most methods.

Why does the same ratio taste different with different beans?

Beans vary in density, roast level, and solubility. Light roasts are denser and harder to extract; you might use a lower ratio (more coffee). Dark roasts are more porous and easier to extract; a higher ratio prevents over-extraction. Origin, processing, and freshness also affect optimal parameters.

How do I dial in a new coffee?

Start with your method's standard ratio. Brew, taste, and adjust. Sour coffee suggests under-extraction—try finer grind or lower ratio. Bitter coffee suggests over-extraction—try coarser grind or higher ratio. Change one variable at a time.

What's the Specialty Coffee Association Golden Cup standard?

The SCA recommends 55 grams of coffee per liter of water (approximately 1:18 ratio) as the starting point for balanced extraction. This produces coffee with 1.15-1.35% Total Dissolved Solids and 18-22% extraction yield—the "Golden Cup" standards for well-extracted coffee.

Does water quality really matter that much?

Absolutely. Water is 98%+ of brewed coffee. Ideal brewing water has moderate hardness (50-175 ppm total dissolved solids), slightly alkaline pH, and no chlorine or off-flavors. Very soft water under-extracts; very hard water over-extracts. If your tap water tastes good, it's probably fine. Otherwise, consider filtered or bottled water.