Log in seconds
Use familiar drink presets or enter caffeine directly in milligrams.
CAFFEINE, MADE VISIBLE
See what remains.
Plan what comes next.
CaffTrace turns your caffeine log into a simple estimate of what may still be in your body—and a practical cutoff estimate built around your bedtime.
Estimated remaining
48 mg
NowBedtime
Follow the trace
See a half-life-based estimate that includes caffeine carried over from earlier drinks.
Plan for bedtime
Get an estimated cutoff time based on your bedtime, reference drink, and preferred threshold.
A CLEARER MODEL
Useful estimates, honestly explained.
CaffTrace uses a simple exponential half-life model. Each logged dose decreases independently over time, then the estimates are added together.
These values are not measurements, diagnoses, or medical safety limits. Metabolism varies, and the model does not reproduce absorption or actual blood concentration.
PRIVATE BY DEFAULT
Your caffeine log stays on your device.
No account and no first-party tracking server. CaffTrace stores your drinks and settings locally. The free app uses Google Mobile Ads; details and privacy choices are described in our policy.
Read the privacy policy →