This bug is more common than you'd think. You start a workout at 11:30 PM. It's going great. You're in the zone. At 12:05 AM, you finish your last set, tap "complete" — and the app shows zero workouts logged.
Why? Because the app's date-handling logic is broken. It timestamped the start to "today" but the finish to "tomorrow," and somewhere in between, your data fell into a crack between two database rows.
Or worse: the app syncs to a cloud server, the server rejects the timestamp as invalid, and your entire session is silently discarded.
IronLog solves this at the architecture level — not with a patch or a workaround:
IronLog has no backend. Your workout data lives entirely in your browser's localStorage — a battle-tested web standard that's been stable for 15+ years. There is no server to reject your data. No sync to fail. No cloud to go down.
When you log a set at 11:58 PM and finish at 12:03 AM, IronLog correctly attributes every rep to the session start date. Cross-midnight workouts are handled natively — because localStorage doesn't have timezone or date-boundary bugs.
Gym in a basement with no signal? IronLog doesn't care — it's 100% offline. Your data is saved to your device the instant you tap "log." No "syncing..." spinner. No "please check your connection." It just works.
Phone battery dies mid-set? Browser crashes? Force-quit the app? Your data was already saved to localStorage the moment you logged it. Reopen IronLog — everything is exactly where you left it.
Paranoid about data loss? Good — you should be. IronLog lets you export your entire workout history as CSV with one click. Save it to your cloud drive. Email it to yourself. Print it out. Your data, your rules.
No other free workout tracker gives you both local-first reliability and one-click data portability.
IronLog is free, no-login, no-ads. Built to solve the problems other apps ignore.
Start Training Free →No account · Works offline · CSV export · Open source