1 · Enter the two zones
intakeA number like +2, -5, or +5.5. Not a city name.
The hours someone would actually take a call.
Your offset while travelling.
Your hours at the destination.
This tool computes in your browser tab. Nothing you type is uploaded, and nothing is stored on our servers — the work stays in this tab. Redact names and identifying details before you paste anything sensitive.
This is a working tool, not professional advice. Check the important outcome with a qualified human before you rely on it.
2 · The strip
readyIntersecting the windows…
Printable strip — $4 one-time
Free tier: unlimited zone pairs, forever.
- Printable strip — both days and the overlap on one card — estimate: ~6 min saved per call.
- Saved zones shelf — up to 8 pairs in this browser — estimate: ~8 min saved per trip.
- Slot message export — a copy-ready line with both times — estimate: ~4 min saved per proposal.
Your one-time purchase stays with you on this device — no account needed, and everything remains private in your browser.