Privacy

StopwatchPro has no accounts and no database. Here is everything that happens with your data.

Stored in your browser

Stopwatch state (so a running watch survives a reload), laps, saved sessions, multiple-stopwatch names, split timer goals, your reaction-test best and stopwatch-game scores are kept in your browser's localStorage under keys starting with swp:. They never leave your device unless you export a CSV yourself.

Pacing analysis (AI)

Only when you press “Analyse my laps”, your lap times (numbers only) and the optional note you type are sent to our server and on to an AI model through Vercel AI Gateway to produce the analysis. We don't store them, and requests are rate-limited per IP address to prevent abuse.

Analytics

We use Ahrefs Web Analytics, a cookieless analytics service, to count page views and see which pages are useful. It does not use cookies or build advertising profiles.

Hosting

The site is hosted on Vercel, which processes standard request logs (such as IP address and user agent) to deliver and secure the site.