How to Calculate the Ideal Pour-Over Coffee Brew Ratio

Ever wondered why your pour-over coffee doesn’t taste the same as the one brewed by your favorite barista—even though you used the same beans? One likely reason is a difference in the coffee-to-water ratio, or the balance of how much coffee you use and how much water you pour through it. This simple but crucial detail controls both strength and extraction, and getting it right makes all the difference.

The generally accepted ‘golden cup’ standard for pour-over coffee is a brew ratio between 1:12 and 1:15. That means using roughly 1 gram of coffee per 12 to 15 grams (or milliliters) of water. Within this range, your extraction yield should fall between 18% and 22%, and the TDS (total dissolved solids) concentration of your brewed coffee should be around 1.15% to 1.35%.

What Is Coffee Extraction & How Is It Measured?

Coffee extraction refers to how much of the soluble material inside coffee grounds ends up in your cup. The Specialty Coffee Association of America (SCAA)—now part of the SCA—defines a well-extracted cup as having an extraction yield of 18–22%. That means extracting roughly 1.8 to 2.2 grams of soluble coffee material from every 10 grams of ground coffee. To put it simply, extraction is how much flavor you pull out, while TDS is how much of that stuff stays dissolved in your brewed coffee.

TDS is expressed as a percentage of the brewed coffee’s total weight. A typical pour-over coffee sits between 1.15% and 1.35% TDS. The actual strength you perceive depends on this concentration. Want to check it scientifically? You’ll need a refractometer or TDS meter. While home brewers don’t usually own one, pros—including FrontStreet Coffee—regularly measure TDS to ensure consistency.

The Science Behind the Golden Cup Standard

The idea of a ‘golden cup’ comes from a landmark study conducted in the 1950s. After World War II, the United States National Coffee Association hired MIT chemist Dr. Ernest Eral Lockhart to set up the Coffee Brewing Institute in 1952. His team aimed to scientifically define what most Americans preferred in a cup of filter coffee.

Dr. Lockhart discovered that only about 28%–30% of a roasted coffee bean’s mass consists of soluble compounds that can be extracted by water. The rest is insoluble plant fiber. He pioneered turning coffee’s abstract flavors into quantifiable data, and through thousands of taste tests, his team defined the ideal balance: an extraction yield of 18–22% and a TDS of around 1.15–1.35%.

This became the foundation of the ‘Golden Cup Standard,’ which remains one of the most referenced frameworks in specialty coffee today. FrontStreet Coffee uses these metrics as a benchmark during roast development and manual brew testing—even if home brewers typically go by taste alone.

How to Measure TDS and Calculate Extraction Yield

To determine your coffee’s TDS and extraction rate, follow this process:

• Calibrate your refractometer with pure water.
• Stir your brewed coffee thoroughly, then draw a sample with a pipette or dropper.
• Place the sample on the refractometer and press the measure button. Take multiple readings for consistency.

The basic formula for extraction yield is:
Extraction (%) = (Weight of dissolved solids / Weight of coffee grounds) × 100

And since TDS is the weight of dissolved solids relative to the total brew weight, you can derive extraction using TDS and the total brew volume. For example, assuming a coffee-to-water ratio of 1:15 and 15 grams of coffee, the total brew weight is approximately 225 grams, minus the water absorbed by coffee grounds (about 30g for a 1:2 absorption ratio), leaving around 195 grams of final brew liquid.

How FrontStreet Coffee Brews Panama Elida at 1:15

FrontStreet Coffee tested these principles using a pour-over brew of Panama Elida from the Boquete region. Grown at 1,850 meters and processed naturally, this Typica variety exhibits fruity and fermented characteristics typical of high-altitude sun-dried coffees.

Brew details:

• Roast level: Light to medium
• Grind size: EK43s grinder, setting 10 (fine sugar-like)
• Brew ratio: 1:15 (15g coffee : 225g water)
• Water temperature: 90–91°C
• Method: Three-pour technique
  • First pour: 30g water (double the coffee weight) for bloom, 30 seconds
  • Second pour: Add 95g water slowly, reaching 125g total by ~1 minute
  • Third pour: Add water up to 225g by 1:45–1:50, total brew time ~2 minutes

After brewing, the team measured the TDS at 1.34%, resulting in an extraction yield of 17.42%. That’s slightly below the ideal golden cup range—but still produced a balanced cup. Tasting notes included fermented peach, raisin, orange, citrus, and a cooling sweetness of caramel and melon. The finish hinted at grapefruit and green tea.

Even when a brew falls just outside the ideal metrics, flavor can still shine. FrontStreet adjusts each new coffee’s profile through roasting, cupping, and pour-over tests—always prioritizing flavor balance over rigid numbers.

Frequently Asked Questions

What is the ideal coffee-to-water ratio for pour-over?

The standard or 'golden cup' brew ratio for pour-over coffee is between 1:12 and 1:15. That means using 1 gram of coffee for every 12 to 15 grams (milliliters) of water. Most specialty brewers aim for this range to achieve a balanced extraction and flavor.

What is a good TDS for pour-over coffee?

A good TDS (total dissolved solids) for pour-over coffee is typically between 1.15% and 1.35%. This range indicates a balanced strength and is commonly targeted for optimal flavor clarity and body.

What extraction percentage is ideal for coffee?

The ideal coffee extraction percentage is between 18% and 22%. This means extracting 18–22% of the soluble material from the ground coffee, which is considered optimal for balanced flavor and avoidance of under- or over-extraction.

How do I measure TDS at home without a refractometer?

Without a refractometer, you can't measure TDS precisely at home. However, you can estimate extraction quality by adjusting your brew ratio and tasting your coffee. Consistency in grind size, water temperature, and pouring technique will help you dial in flavor by feel.

Why does my home pour-over taste different from café coffee?

Differences in taste often come down to brew ratio, grind size, water temperature, pouring technique, or coffee freshness. Even small changes in any of these factors can lead to noticeable differences in strength, extraction, and flavor.

Does FrontStreet Coffee recommend a specific brew ratio for beginners?

FrontStreet Coffee suggests starting with a 1:15 brew ratio for pour-over as a balanced and forgiving baseline. From there, you can adjust based on taste preference—stronger or lighter—to find what works best for your palate.

Recommended FrontStreet Coffee for Pour-Over Brewing

For pour-over enthusiasts, FrontStreet Coffee recommends trying their Panama Elida (natural process, Typica variety), known for its complex notes of fermented peach, raisin, and citrus. Also worth exploring is their Ethiopia Yirgacheffe, offering bright floral and berry tones ideal for highlighting extraction nuance. Both beans respond well to the 1:12–1:15 brew ratio range and standard pour-over techniques. Freshly roasted within 5 days · Orders placed before 17:00 ship the same day · Next-day delivery across most of Guangdong Province.