Coffees to Offset Lost Sleep
A tongue-in-cheek calculator for how many coffees it would take to 'offset' a night of lost sleep, at five coffee strengths from weak to very strong.
Frequently asked questions
Is this tool free?
Yes. Calchemy tools are free to use in your browser.
Is my data uploaded?
No. The tools are designed to run locally in your browser unless clearly stated otherwise.
Can coffee actually offset lost sleep?
Not really - caffeine can mask tiredness for a while, but it doesn't repay sleep debt the way sleep itself does. This tool is for fun, not sleep science.
What caffeine amount does this assume per coffee?
It depends on the strength you pick: about 65mg per cup for weak (strength 1), 80mg for mild (2), 95mg for average (3, a typical standard brewed coffee), 120mg for strong (4), and 150mg for very strong (5). Espresso, cold brew and specialty drinks vary a lot in real life.
Why do the results differ by strength?
The 'total caffeine needed' is the same underlying target either way - it's just divided into fewer, stronger cups at higher strengths, or more, weaker cups at lower strengths.