Sleep Cycle Calculator

Find the best bedtime for a wake-up time (or vice-versa) based on 90-minute sleep cycles, so you wake up between cycles feeling more rested. Runs in your browser.

Runs in your browser — your file never leaves your device

Frequently asked questions

Is Sleep Cycle Calculator free to use?

Yes — Sleep Cycle Calculator is completely free with no limits, no watermarks and no sign-up. It runs in your browser, so there is nothing to pay for.

Are my files uploaded or stored anywhere?

No. This tool does all its work locally in your browser using your own device's power. Your files never leave your device and we never see them.

Do I need to install anything or create an account?

No installation and no account needed. Sleep Cycle Calculator works on any modern browser — Windows, Mac, Linux, Android and iPhone.

How do I use Sleep Cycle Calculator?

Open the tool, add your file (or paste your content), adjust any options, then press “Calculate sleep time”. Your result is ready to download in seconds.

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