What a Coffee Ratio Really Controls
A coffee ratio is the simplest, most repeatable way to control strength. When people say “1:16,” they mean one part coffee to sixteen parts water by weight. In practical terms, if you use 20 grams of coffee, a 1:16 recipe uses 320 grams (about 320 ml) of water. Ratio does not directly tell you whether a cup will be sweet or bitter, but it sets the concentration range your brew can land in. Once the ratio is consistent, you can adjust grind size, brew time, agitation, and water temperature to change extraction without constantly guessing why a cup tastes different.
Most brewing variables are connected. If you change dose, you often change flow rate, contact time, and bed depth. If you change water volume, you change turbulence and the way coffee extracts. Ratio helps you anchor those moving parts. It makes experiments meaningful: if you keep ratio constant and adjust grind, you learn about extraction. If you keep grind constant and adjust ratio, you learn about strength. The Coffee Ratio Calculator exists to make those changes intentional and repeatable.
Filter Brew Ratio vs Espresso Brew Ratio
“Coffee ratio” can mean two different things depending on how you brew. For filter methods (pour-over, drip, French press, AeroPress in a filter style), ratio usually means coffee dose compared to brew water. You put water in, some stays in the grounds, and you get a brewed yield that is slightly lower than the water you poured. For espresso, ratio typically means beverage yield compared to coffee dose. A common espresso target is 1:2, meaning a 18 g dose yields about 36 g of espresso in the cup.
The distinction matters because the numbers look similar but behave differently. A 1:16 filter recipe is not comparable to a 1:2 espresso recipe. In espresso, a small change in ratio can strongly change body and intensity. In filter brewing, ratio changes move strength, while flavor balance often responds more to extraction control. That is why this tool separates filter brewing from espresso ratio and gives you a dedicated tab for each.
Why Brewed Coffee Output Is Lower Than Brew Water
When you pour water onto coffee grounds, the grounds absorb and retain a portion of that water. Even after dripping stops, the bed holds liquid. This is one reason a recipe that uses 320 ml of water might produce 280–300 ml in the cup. The amount retained depends on grind size, brew method, coffee freshness, and filter type, but a practical baseline is around 2 ml retained per gram of coffee.
If you want a specific final cup size, you can work backward. Instead of guessing how much water to pour, estimate how much water will be retained and add that to your target yield. The Filter Brew tab does exactly that: it uses your ratio plus an absorption setting to estimate the brew water required to reach your target brewed output. You can keep absorption at the standard value or customize it after a few brews with your equipment.
Common Ratio Ranges and What They Taste Like
Ratios are best thought of as a spectrum. Lower ratios (like 1:14 or 1:15) use more coffee per unit of water and usually produce a stronger, fuller cup. Higher ratios (like 1:17 or 1:18) use less coffee per water and often taste lighter and more tea-like. Neither is “correct.” The right ratio depends on roast level, bean density, brew method, and your preference.
As a simple starting point, many people find these ranges useful:
- 1:14 to 1:15 for bold, rich cups and darker roasts, or when you want more body.
- 1:15.5 to 1:16.5 as an all-purpose range for most medium roasts and everyday brewing.
- 1:17 to 1:18 for lighter cups, bright coffees, or when you want clarity and less intensity.
If your coffee tastes thin or watery, you can move to a lower ratio (more coffee). If it tastes too intense, move to a higher ratio (more water). Then fine-tune extraction with grind size and brew time. The most efficient workflow is to find a ratio you like first, then dial extraction until sweetness and balance appear.
How to Use the Filter Brew Tab
Start by selecting your brew method. The calculator can suggest a sensible ratio range mentally, but you control the exact ratio number. Next, choose your target brewed coffee volume in ml, cups, or fluid ounces. If you want one mug, you might set 300 ml. If you want a small carafe, you might set 500–800 ml.
Set your brew ratio as “1 : X.” If you choose 16, the tool uses 1:16. Then decide whether you want to account for absorption. If you set absorption at 2.0 ml per gram of coffee, the calculator will estimate extra brew water to pour so you still reach your target yield in the cup. If you prefer to ignore yield estimation and simply want the classic math, set absorption to 0 and the calculator will treat target as brew water.
Extra loss exists for edge cases: some systems lose water to pre-rinse, a dripper that holds liquid, or evaporation in long brews. Most of the time you can leave it at 0%. If you do long batches or consistent losses, a small number like 1–3% can help your final yield match what you expect.
How to Use the Espresso Ratio Tab
Espresso is about controlling dose, yield, time, and grind. The espresso tab lets you do three common tasks. First, you can calculate ratio from your actual dose and yield, which is perfect for logging shots. Second, you can enter a dose and a target ratio to calculate the yield you should stop at. Third, you can enter a yield and a target ratio to compute the dose needed.
Ratios around 1.7–2.0 often feel thicker and more concentrated (ristretto to normale). Ratios around 2.3–2.7 often feel more open and higher volume (lungo). Taste still depends on extraction. If a shot tastes sour, you likely need more extraction (finer grind, longer contact time, or higher temperature), not necessarily a different ratio. If it tastes bitter and harsh, you may be over-extracting (coarser grind, shorter time). Ratio sets the body and intensity range; extraction sets the sweetness and balance.
Ratio Finder: Recreating a Great Cup
The hardest part of home brewing is repeating a cup you loved. People remember flavor, but they forget numbers. The Ratio Finder tab is designed for that: enter your coffee amount and water amount in the units you used, and it calculates your effective ratio. It also estimates brewed yield using absorption so you can see what you likely got in the cup.
The Finder tab also gives you a strength-style summary that is easy to compare: grams of coffee per liter of water and approximate positioning on the ratio spectrum. That turns a “nice cup” into a repeatable recipe. Once you can repeat it, you can improve it by changing one variable at a time.
Scaling Recipes Without Guesswork
Scaling is where ratios shine. If you know you like 1:16 for your beans, you can brew 250 ml or 1 liter and the character stays similar. The Quick Table tab produces fast options for a chosen brew size across several common ratios so you can choose the strength you want in seconds.
Scaling is also how you keep brewing consistent across different gear. A small dripper might work best with 15–25 g doses, while a larger brewer might behave better at 30–60 g. If you scale too far outside a brewer’s sweet spot, flow and extraction can change. Use ratio as the baseline, then pay attention to whether your equipment likes the dose range you are asking it to handle.
Units: Why Coffee People Prefer Grams
Grams are the standard for good reason. Coffee beans are irregular, scoops vary, and “tablespoons” are not consistent. With a scale, 20 grams is always 20 grams. Water is also easy: 1 ml is approximately 1 gram, so you can weigh water instead of reading a measuring cup. This calculator supports cups and ounces because people use them, but if you want the most repeatable brewing, move toward grams for coffee and grams or ml for water.
If you do use cups, remember there are multiple “cup” definitions. The calculator uses 240 ml as a practical standard. If your brewer’s “cup” marking is different, use ml instead. You will get more consistent results and less confusion when recipes come from different regions.
How to Dial In Flavor After the Ratio Is Set
Once your ratio is stable, use taste to decide the next move. If your brew tastes sour, sharp, or underdeveloped, you usually need more extraction: grind finer, increase contact time, or increase water temperature slightly. If it tastes bitter, astringent, or harsh, you may be extracting too much: grind coarser, reduce time, or reduce agitation. If it tastes both bitter and sour, your extraction may be uneven; improve pouring technique, stir gently, or ensure your bed is evenly saturated.
Ratio changes are best used to control strength, not to fix extraction problems. A weak but well-extracted cup can be improved by lowering the ratio slightly. A strong but under-extracted cup will still taste unpleasant; it needs extraction improvements first. This is why coffee professionals separate “strength” and “extraction” as different concepts and solve them in a sequence.
Practical Starting Recipes You Can Trust
If you want a fast starting point, these recipes are broadly useful:
- Pour-over: 20 g coffee, 320 g water (1:16), medium-fine grind, pour in pulses, total time around 2:45–3:30.
- Drip machine: 60 g coffee per liter of water (about 1:16.7), medium grind, ensure proper basket and filter fit.
- French press: 30 g coffee, 450 g water (1:15), coarse grind, steep 4 minutes, plunge slowly.
- AeroPress: 16 g coffee, 240 g water (1:15), medium-fine grind, steep 1:30–2:00, press gently.
- Espresso: 18 g dose, 36 g yield (1:2), adjust grind for your machine and target time.
Use the calculator to scale any of these without changing the underlying ratio, then tweak based on your taste and equipment.
Limitations and the Best Way to Personalize the Numbers
No calculator can perfectly predict a specific brewer’s retention, flow behavior, or taste outcomes. That is why this tool keeps absorption editable and treats extra loss as optional. The best approach is to brew once, measure your actual yield if you care about it, and then update absorption so the target yield model matches your reality.
Once the tool matches your setup, you get a powerful advantage: you can set a cup size goal, press calculate, and brew consistently without mental math. That frees you to focus on coffee quality and technique instead of repeatedly doing conversions. The result is less variability, fewer disappointing brews, and faster dialing when you change beans.
FAQ
Coffee Ratio Calculator – Frequently Asked Questions
Quick answers about ratios, units, yield, espresso targets, and how to scale recipes reliably.
A coffee ratio (brew ratio) is the relationship between coffee dose and water used. For filter coffee it’s usually written as 1:15, 1:16 or 1:17, meaning 1 gram of coffee for every 15–17 grams (ml) of water.
A common starting range for pour-over is 1:15 to 1:17. Use a lower number (like 1:15) for a stronger cup and a higher number (like 1:17) for a lighter cup, then adjust based on taste.
For brewing calculations, water is commonly treated as 1 ml ≈ 1 gram, which is accurate enough for coffee. That makes ratios easy because you can use ml and grams interchangeably for water.
Coffee grounds absorb and retain water, and some water can be lost to evaporation or drips. This calculator can estimate brew water needed for a target cup size using an absorption setting.
Filter brew ratio compares coffee dose to brew water (1:15, 1:16, etc.). Espresso brew ratio compares coffee dose to beverage yield (like 1:2 or 1:2.5), which is a different measurement used for espresso.
Choose a ratio, set your target brew size, and the calculator scales the coffee dose and water. You can also scale by number of cups or by carafe size in ml or oz.
French press often starts around 1:14 to 1:16 depending on preference, grind size and steep time. The best ratio is the one that matches your beans and taste, so use this calculator to dial in.
Use the Ratio Finder tab. Enter your coffee dose and your water amount and it returns your effective ratio and a strength-style summary so you can repeat or adjust it next time.
Grind size changes extraction, not the math of the ratio. If your coffee tastes sour or weak, you might grind finer or increase contact time. If it tastes bitter or harsh, grind coarser or reduce contact time, then fine-tune ratio last.