About FastWindowTimer
FastWindowTimer is a free intermittent fasting timer and calculator. There's no account, no app to install, and no paywall. It works in your browser and saves your history locally on your device.
Why this site exists
Most fasting apps require an account, a subscription, or push you toward upsells. We built FastWindowTimer as a genuinely free tool — one you can open in any browser, start a fast with one tap, and close when you're done. The goal is a fast, clean, trustworthy tool for anyone practising intermittent fasting.
Free, unbiased, no account
FastWindowTimer is free to use. There are no premium tiers, no sign-up prompts, and no health-claim advertising. Any affiliate links or ads added in future will be clearly disclosed. The tool runs on your device: your fasting history stays in your browser's local storage and is never sent to a server.
Who runs it
FastWindowTimer is maintained by a small independent editorial team. Content is researched and written by the editorial team and cited to authoritative sources. We do not currently have a named medical reviewer — health content is kept conservative and heavily sourced until a credentialed reviewer is in place. See our editorial policy for details.
Published 2026-06-21. Content reviewed by the FastWindowTimer editorial team.