Coffee Roast Weight Loss Calculator
Pick the roast level and how you brew, and optionally enter the roast date from your bag. We show how many days to rest the coffee, when it peaks, and the calendar dates.
Rules of thumb that vary with green moisture, batch size and roaster. Track your own batches.
How much weight does coffee lose when roasting?
Coffee typically loses 11 to 20 percent of its weight, mostly water driven off as steam. Light roasts lose about 11 to 14 percent, medium roasts 14 to 16 percent, and dark roasts 16 to 20 percent or more.
How do I calculate roast weight loss?
Subtract the roasted weight from the green weight, divide by the green weight, and multiply by 100. For example, 500 g of green coffee that weighs 425 g after roasting lost 15 percent.
How much green coffee do I need for 1 lb of roasted coffee?
For a medium roast losing about 15 percent, you need roughly 534 g (1.18 lb) of green coffee for 454 g (1 lb) of roasted coffee. Use the target mode above to get the number for your roast level.
Why does my roast loss differ from the table?
Moisture content of the green coffee, batch size, roaster type and how long development lasts all move the number. Track your own losses batch by batch: consistent loss at a given profile is a good sign of repeatable roasts.
Does weight loss tell me the roast level?
It is a useful cross-check, not a replacement for color and sound. Our catalog lists 290 light, 261 medium and 68 dark roasted coffees if you want a reference for the flavors each level produces.