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Sleep Cycle Calculator

Find optimal bedtime based on sleep cycles.

Best bedtimes (cycles of 90 min):

  • 21:46 (6 cycles)
  • 23:16 (5 cycles)
  • 00:46 (4 cycles)
  • 02:16 (3 cycles)

Frequently asked questions

Is Sleep Cycle Calculator really free?

Yes — Sleep Cycle Calculator is 100% free with no signup, no watermarks, and no usage limits on the basic version.

Is Sleep Cycle Calculator safe to use?

Your files are processed in your browser whenever possible and never stored on our servers.

Does Sleep Cycle Calculator work on mobile?

Yes — it works on iPhone, iPad, Android, Windows and Mac in any modern browser.

Do I need to install anything?

No. Sleep Cycle Calculator runs entirely in your browser. No download, no extension, no account.

What's the difference between Free and Pro?

Free covers the core Sleep Cycle Calculator features with reasonable daily limits. Pro removes limits, lifts the file-size cap, and unlocks batch processing and embed widgets.

Other ways people use Sleep Cycle Calculator

Popular long-tail searches — each opens a tailored landing page for that use case.

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