Independent reference · Reviewed September 6, 2026
Brew better coffee at home, with numbers
Five topic pages covering ratio, grind, water, method, freshness and caffeine, with every figure taken from published coffee standards rather than from habit.
The Home Coffee Bench is a practical guide to brewing coffee at home with a scale, a grinder, water and a repeatable method. Its focus is not a single recipe. It is a way to connect what you can measure with what you taste, so a promising cup can be repeated and an uneven cup can be adjusted without guesswork.
Ratio, grind, water and method are linked. Changing one can alter how quickly water moves, how much coffee dissolves and how strong the finished drink feels. The guide separates those effects into manageable steps, using the brewer and tools already available at home. The aim is clear observation, not equipment collecting or complicated ritual.
The figures on this site provide useful boundaries rather than a promise that every cup will taste the same. Coffee, water and brewing devices behave differently, so begin with a sound baseline and change one variable at a time. Topic pages then take each part further, while this homepage shows how the pieces fit together.
Why the numbers matter
A measured brew gives you a shared language for taste. Strength describes how much dissolved coffee is in the drink, while extraction describes how much of the dry coffee has entered the water. Ratio connects the amount of coffee to the amount of water. These measures do not replace tasting, but they help explain why two cups made from similar beans can feel very different.
Without measurements, a change in flavour can be difficult to trace. A cup may be weaker because more water was used, or it may taste sharp because the grind and contact conditions limited extraction. Recording dose, water amount, temperature and method makes the next brew a controlled comparison. Small adjustments become useful when the starting point is known and the result is described plainly.
The four variables
The guide treats ratio, grind, water and method as the main working variables. Ratio sets the relationship between dry coffee and brewing water. Grind affects the available surface area and the path water takes through the bed. Water carries flavour from the grounds. Method determines the sequence, movement and contact pattern that bring those elements together.
These variables should be read as a system rather than isolated controls. A finer grind can change flow and extraction, while a different method can alter how evenly water reaches the coffee. Start with one change, keep the other conditions steady, and record the result. That approach makes taste easier to connect with an observable brewing choice.
- Ratio: the measured relationship between dry coffee and brewing water
- Grind: the particle size that shapes flow and contact
- Water: the carrier, temperature and chemistry behind extraction
- Method: the brewer, sequence and movement used during brewing
What the Golden Cup window says
The SCA Golden Cup window gives a useful reference for brewed coffee. Its target strength is 1.15-1.35 percent TDS, and its extraction target is 18-22 percent. The table also shows a brew ratio of 55 g of coffee per litre of water, plus or minus 10 percent. These figures describe a practical centre, not a compulsory taste preference.
Water temperature belongs in the same picture: the published window is 91-96 C, or 195-205 F, measured in the brewer. Water should be clean and odour free, with no chlorine or chloramines. Use the table as a diagnostic frame. If a cup tastes thin, harsh or unbalanced, the numbers can help identify which part of the process deserves attention.
| Brew strength (TDS) | 1.15-1.35 percent, that is 11.5-13.5 g of dissolved solids per litre |
|---|---|
| Extraction yield | 18-22 percent of the dry coffee mass dissolved into the cup |
| Brew ratio | 55 g of coffee per litre of water, plus or minus 10 percent |
| Brew water temperature | 91-96 C, that is 195-205 F, measured in the brewer |
| Brew water | clean, odour free, no chlorine or chloramines |
Choosing a method for your morning
Choose a method by the kind of control and routine it offers. A brewer that makes water movement visible can help you study flow and contact. A more contained design may make a repeatable morning sequence easier. The best starting method is the one that can be prepared consistently, measured clearly and cleaned without disrupting the rest of the routine.
Keep the method stable while learning the other variables. Use the same brewer, the same scale and a consistent way to add water before changing grind or ratio. If the cup changes, the record should show what changed with it. Method pages can then explain their particular strengths, but the homepage principle remains simple: make the process repeatable before making it elaborate.
Water, beans and freshness
Water is more than a neutral carrier. Its smell and chemical character can appear directly in the cup, and chlorine or chloramines can interfere with a clean result. The Golden Cup reference calls for clean, odour-free brewing water. If tap water has a noticeable smell, compare it with a cleaner source while keeping the coffee, ratio and method unchanged.
Beans also change as they move through storage and degassing. Freshness is therefore part of the measurement record, alongside dose and grind. Roaster guidance supplies useful storage and degassing windows, but the cup remains the practical check. Keep storage conditions steady, note the roast information available to you, and avoid blaming the grinder when the coffee itself has changed.
How to use this guide
Begin with the overview and the Golden Cup table, then select the topic that matches the problem in the cup. Measure coffee and water, note the method, and make one deliberate adjustment. Taste the result before changing anything else. This creates a short learning loop: observe, change, brew and compare.
The topic pages are designed to work together rather than as disconnected recipes. Use ratio to establish a starting relationship, grind to manage flow and extraction, water to remove a source of unwanted flavour, and method to make the sequence repeatable. Keep notes in the units shown by the table, and treat the figures as reference points for better decisions.
Frequently asked questions
What ratio should I start with?
Start near the Golden Cup reference of 55 g of coffee per litre of water, with a permitted range of plus or minus 10 percent. Measure both ingredients rather than relying on volume. Keep the method and grind steady, taste the result, then adjust the relationship if the cup seems too strong or too weak.
Why does my coffee taste sour?
Sourness can indicate that extraction has not reached enough of the coffee material, though taste alone cannot identify the cause with certainty. Check the grind, water temperature, contact conditions and ratio. Change one factor at a time, keeping the dose and method recorded so the next cup provides a useful comparison.
Why does my coffee taste bitter?
Bitterness can appear when extraction is pushed too far, but an unpleasant result may also come from water, beans or an uneven process. Review grind, contact and temperature against the method instructions. Make one modest change, preserve the other measurements, and compare the new cup with the previous result.
Do I need a burr grinder?
A burr grinder is not required to begin measuring coffee at home. Consistency matters because uneven particles can make flow and extraction harder to interpret. If the grind varies widely, focus first on repeatable brewing and clear notes. A more consistent grinder can make later adjustments easier to understand.
Is tap water fine for brewing?
Tap water can be suitable when it is clean and free from noticeable odour, chlorine and chloramines. Water quality varies, so the cup and smell are useful checks. If the water affects flavour, compare another clean source while holding the coffee, ratio, temperature and brewing method steady.
How long after roasting should I brew?
There is no single day count given here for every coffee. Beans release gas after roasting, and roaster guidance provides the relevant storage and degassing window. Follow that guidance, record the roast information available, and judge the cup alongside grind, ratio and water rather than treating freshness as an isolated number.
The Home Coffee Bench keeps home brewing grounded in measurable choices: ratio, grind, water and method. It is an independent, non-commercial reference from jdrcr.com, with this version reviewed on September 6, 2026. Use the figures as boundaries, taste carefully, and build a repeatable process one adjustment at a time.
How this guide is built
Every figure on this site is checked against a named public reference before publication. Brewing strength, extraction yield, ratio, water temperature and water chemistry follow the Specialty Coffee Association standards. Espresso parameters follow published dose, yield, temperature, pressure and time references. Caffeine amounts and decaffeination routes follow food-science and published reference material. Storage and degassing windows follow roaster guidance. The reference families are listed on the about page. Last reviewed: September 6, 2026.