Free coffee calculator
Espresso shot checker
Enter the dry coffee dose, the weight of espresso in the cup, and the shot time. The checker shows the ratio and the average flow, and says whether the time sits in the usual window.
Try it: shot checker
Is the shot running in the usual window?
Ratio
1:2
Flow
1.3 g/s
The time is in the usual window, so taste decides. Only change the grind if the cup is off.
How it works
Ratio = yield (g) ÷ dose (g). Average flow = yield (g) ÷ shot time (s).
An 18 g dose that gives 36 g in 28 seconds is a 1:2 shot flowing at about 1.3 g per second. Many espresso recipes start around 1:2 in 25 to 30 seconds.
The time window is a clue, not a target. A fast shot that tastes sour usually needs a finer grind. A slow shot that tastes bitter or dry usually needs a coarser grind. If the shot tastes good, keep it.