REM Sleep Estimate Calculator

About this calculator

REM (rapid eye movement) sleep is the stage most associated with dreaming and memory consolidation, and it typically makes up roughly 20–25% of total sleep time in healthy adults, occurring in cycles of about 90 minutes that repeat through the night with REM periods growing longer toward morning. The actual share varies by age (infants spend far more time in REM), sleep quality, and factors like alcohol or certain medications that suppress it.

This calculator takes your total sleep hours and a REM percentage and estimates how many minutes of REM sleep you're getting on a typical night. Sleep-tracker users cross-checking a wearable's readout, people investigating their own sleep architecture out of curiosity, and sleep-health enthusiasts use it as a quick estimate — not a diagnostic tool, since only a clinical polysomnography study measures REM directly.