The SleepLabix Editorial Team

Editorial · SleepLabix

SleepLabix is a sleep-cycle calculator maintained by a small in-house group that also writes its articles — the same hands on the tool and on the page.

Coverage sticks to Sleep Tools. In practice it suggests bedtimes and wake times that land at the end of a ninety-minute sleep cycle rather than in the middle of one. Typical runs through it include picking a bedtime for a fixed alarm, working out when to wake after going to bed now and testing whether a schedule gives whole cycles.

Articles are reviewed for two failure modes: a method that does not reproduce, and phrasing that could be taken as advice. Topics that drift into regulated territory stay on the numeric side, with a pointer to a qualified professional.

Report a problem to support@sleeplabix.com and it goes straight to the group that produced the article. The fix, if one is needed, is made where the reader will see it.

Recent articles

Are Sleep Cycle Calculators Accurate? Limitations of the 90-Minute Rule for Different Chronotypes

You set your alarm for 7:00 AM, calculated backward in 90-minute blocks, and landed on a bedtime of 10:00 PM. Clean math. You wake up groggy anyway, wondering if you somehow miscalculated.

Sleep Cycle Calculators and Sleep Latency: Factoring In How Long It Takes to Fall Asleep

You set your alarm based on a sleep cycle calculator. It told you that 7.5 hours would land you perfectly at the end of a 90-minute REM cycle. You followed the math. You went to bed at 10:30 PM.

8 Hours and Still Tired? Using a Sleep Calculator to Fix Interrupted REM Cycles

Here's the thing nobody tells you about the magical "8 hours" rule—it's mathematically hostile to your REM cycles. A full sleep cycle runs roughly 90 minutes. Eight hours is 480 minutes.

The 90-Minute Sleep Cycle Rule: The Core Science Behind Bedtime Calculators

That's the question I get asked more than any other from people building personal sleep schedules or fine-tuning their own bedtime calculator spreadsheets.

Sleep Inertia Explained: Using a Sleep Calculator to Prevent Heavy Morning Grogginess

Quick tip before we dive in: set your alarm for a multiple of 90 minutes from when you actually fall asleep—not from when you get into bed.

Calculating Sleep Cycles for a 12-Hour Shift: How Many 90-Minute Blocks You Actually Need

Your alarm screams at 5:45 PM. You're staring at the ceiling in a room you blacked out with garbage bags and duct tape, wondering if you actually slept or just lay there having anxiety dreams about IV pumps.

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