Sleep Cycle Calculator

Working

Free bedtime and wake-up planner based on 90-minute REM cycles.

Runs in the browser1 checkEveryday tools

Open Sleep Cycle CalculatorChecked 2 days ago

What stands out

Taken from the page and the access facts we recorded. Nothing here is guessed.

pick a bedtime from 90-minute cycles
time a 20, 60, or 90-minute nap
No account required
Free

What we checked

A missing tick means we have not measured it. A red mark is a check that failed.

App accessible
The last check reached a working page.
Page rendered
The last browser pass found a page that rendered.
Screenshot kept
We captured a picture of the page.

Looked: 0
Opened: 1
Checks: 1
Watching: 0

Looked and opened count distinct browsers on this site, not verified people. Checks are requests we made. None of these come from the app itself.

Screenshot of Sleep Cycle Calculator — Screenshot from our last capture

Evidence

Each bar is one request we made

Checks: 1
Working: 100%
Median response: 448ms
Watching since: 2 days ago

Browser render check

Checked 13 hours ago in a real browser

5 pages rendered

/rendered530ms
/en/blogrendered443ms
/en/blog/science-behind-sleep-cyclesrendered419ms
/en/blog/sleep-hygiene-tipsrendered380ms
/en/toolsrendered550ms

Pages loaded in a real browser, not just an HTTP request. Route discovery is best-effort — nav links not in the initial DOM are not followed. How we check

Activity

Watching since 2 days ago

Last content change: None seen yet
Unchanged for: 2 days
Certificate expires: in 76 days

We hash the visible text on every check, so a redesign registers and a rotating advert does not. An app that has not changed in a long time is not necessarily abandoned — but it is a fact worth knowing before you depend on it.

What it does

This calculator finds bedtimes and wake-up times from 90-minute sleep cycles so you can plan 4–6 cycles instead of waking mid-sleep. Bedtime, wake-up, and nap modes include a fall-asleep buffer. It runs in the browser with no sign-up.

What people say

No reviews yet.

We would rather show none than invent them.

Embed this status

Put it in your README. It updates itself every time we check, and links to your verification record — evidence a stranger can read, not a page selling them something.

[![Sleep Cycle Calculator — still works](https://itstillworks.cruscible.com/api/badge/sleep-cycle-calculator)](https://itstillworks.cruscible.com/verify/sleep-cycle-calculator)

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