Back
Fastkeep

Fastkeep

Forgot to start? Fix it anytime.

An intermittent fasting timer whose records you can edit. Start in one tap, correct any past window, and keep a log that matches what you actually did - no subscription.

Get it on Google Play

Screenshots

Home screen with the circular countdown showing 3 hours 27 minutes left on a 16:8 fast, a 13-day streak chip and the fat-burning stageThe edit sheet open over the timeline, with the fasting/eating toggle, start and end times all editableTimeline tab with a week calendar and a day detail listing each window, water intake and weightThe fasting stages sheet listing all six phases with the current one markedInsights tab showing fasts completed, average duration, goal-reached ratio and a weekly chart against the 16-hour goalThe fasting plans sheet with 16:8, 18:6, 20:4, OMAD, count-up and a custom 14:10 planThe same home screen in the dark theme, at nightSettings in the dark theme, showing units and the CSV data export

Fasting habits do not break because you lack willpower. They break because you forget to press start, forget to press stop, and end up with a log that no longer matches reality. Fastkeep is built around that one problem.

How it works

  1. 1Open the app and tap once - no sign-up, no onboarding quiz, no account.
  2. 2The countdown to your goal runs to the second, and keeps running after you close the app or restart your phone.
  3. 3Forgot to start or stop? Tap the window in the Timeline and change its start, its end, or its type.
  4. 4Missed a whole day? Add the window straight from the calendar - the app only blocks what is genuinely wrong: overlaps and times in the future.
  5. 5When a fast ends, log how it felt in one screen - mood, energy and a note - or skip it.

Why Fastkeep

  • Every window stays editable, so a forgotten tap never costs you the record.
  • No subscription. Every fasting plan, every statistic and the CSV export are open to everyone.
  • No account and no cloud - everything is stored on your device.
  • One notification when your fast is done, plus an optional daily reminder. Nothing else.
  • A stage strip shows where you are in the fast, with the time left to the next phase.

What's inside

  • One-tap start with a to-the-second countdown that survives app closes and restarts
  • Full editing of any past window - start, end, type, or delete
  • A month calendar with every fasting and eating window drawn as a bar
  • Six metabolic stages - fed, glycogen use, fat burning, ketosis, autophagy and deep fast - with time to the next (informational only, not medical advice)
  • Preset plans 16:8, 18:6, 20:4 and OMAD, plus count-up mode and custom plans with any number of hours
  • Insights: current streak and streak freezes, longest fast, average duration, goal-reached ratio and a weekly chart
  • Water and weight logging per day, with a weight trend chart
  • A journal for each fast - mood, energy and a note
  • CSV export of every window, weight and water entry

Start a fast in one tap, fix the ones you forgot, and keep a log you can trust.

Frequently asked questions

Does Fastkeep cost anything?

The app is supported by a small banner and one full-screen ad when you open it - never while you are starting or ending a fast. A single purchase removes every ad permanently. There is no subscription and nothing else is locked behind it.

Who is it for?

Anyone doing intermittent fasting who wants a timer that does not force a sign-up, does not sell a subscription, and lets them correct the records they forgot to log.

What happens to my data?

Everything stays on your device. There is no account, no cloud sync and no sharing. You can export every window, weight and water entry to CSV at any time.

Does the timer keep running if I close the app?

Yes. The countdown is derived from the wall-clock start time, so closing the app or restarting your phone does not affect it, and a notification fires when the fast is done.

Which platforms is it on?

Fastkeep is available on Android, in ten languages: English, Korean, Japanese, German, French, Spanish, Portuguese, Italian, Simplified Chinese and Traditional Chinese.

Legal