Coffee Brewing Chart: The Ultimate Guide for Better Coffee

History, How to Read It, and Practical Tips

A coffee brewing chart is one of the most useful tools for understanding the relationship between coffee strength, extraction, and flavor balance. Whether you are a home brewer or a professional barista, mastering it can significantly improve consistency and the quality of your coffee.

The Origin of the Coffee Brewing Chart

The coffee brewing chart was first developed in the 1950s by Dr. Ernest E. Lockhart, a professor at MIT working with the Coffee Brewing Institute (CBI), the predecessor of today’s Specialty Coffee Association (SCA).

Lockhart used scientific measurements like TDS (Total Dissolved Solids) and extraction yield to quantify coffee brewing. His work formed the foundation for the Coffee Brewing Control Chart, which is still used today as a benchmark for coffee quality and barista training.

What Is a Coffee Brewing Chart?

A brewing chart is a visual guide that maps coffee brews based on two main variables:

•   Extraction Yield (%) – how much flavor has been extracted from the coffee grounds

•   TDS (Total Dissolved Solids) – how concentrated or strong the coffee is

 

Coffee Brewing Chart

 

Understanding the Axes

Extraction Yield (X-axis)

•   Low → under-extracted coffee

•   High → over-extracted coffee

•   Ideal range: 18–22%

TDS (Y-axis)

•   Low → weak, light coffee

•   High → strong, concentrated coffee

•   Typical ranges:

•   Espresso: 8–12%

•   Filter / Pour-over: 1.15–1.45%

By combining these two variables, the chart helps brewers understand why a coffee tastes too sour, too bitter, or just right.

Coffee Brewing Control Chart

How to Use a Coffee Brewing Chart

Brewing charts allow you to:

•   Diagnose flavor problems

•   Adjust grind size, brew ratio, or brew time

•   Compare brewing methods (espresso, pour-over, French press, AeroPress)

•   Improve consistency across batches

Example adjustments:

•   Sour coffee? Increase extraction (grind finer, brew longer, warmer water)

•   Bitter coffee? Decrease extraction (grind coarser, shorter brew, cooler water)

•   Weak coffee? Increase TDS by adjusting coffee-to-water ratio

Do You Need a Refractometer?

While a refractometer measures TDS precisely, you can still use the brewing chart conceptually. Even without exact measurements, it guides decision-making and helps brewers understand the relationship between strength, extraction, and taste.

Why Coffee Brewing Charts Are Still Relevant

•   They turn coffee brewing from an art into a science

•   Provide a foundation for SCA barista training and quality control

•   Help understand the interplay between TDS, extraction yield, and flavor

•   Improve consistency and repeatability in every cup

Conclusion

The Coffee Brewing Chart is more than a technical diagram—it is a practical framework to brew balanced and flavorful coffee. Understanding its history, axes, and application allows brewers to troubleshoot issues, adjust recipes, and achieve consistent results, whether at home or in a professional setting.

Mastering the coffee brewing chart is a key step toward smarter, more predictable, and enjoyable coffee. ☕