Days Until Since
Calculate date and time values locally with visible assumptions and copy-ready results.
Use calendar math with the assumption visible
Use it for milestones, renewals, anniversaries, launches, trips, school dates, and simple countdown copy. This tool uses local midnight so the count answers a calendar-day question rather than an exact-hour countdown.
The tool compares the selected date with today at local midnight and returns a signed day count. Future dates are days until; past dates are days since. The signed output makes one page handle both future milestones and past anniversaries without changing modes.
Limits and local processing
It counts calendar-day boundaries, not exact hours remaining unless today has already passed in your timezone. The target date is compared locally with today in the browser. If a deadline closes at a specific hour, use a countdown timer instead of a day-only result. The signed wording is useful for copy because it avoids manually changing ?until? to ?since? after a milestone passes. It stays simple on purpose.
Frequently Asked Questions
How does the days until since work?
The tool compares the selected date with today at local midnight and returns a signed day count. Future dates are days until; past dates are days since.
When should I use this tool?
Use it for milestones, renewals, anniversaries, launches, trips, school dates, and simple countdown copy.
What should I watch out for?
It counts calendar-day boundaries, not exact hours remaining unless today has already passed in your timezone.
Is this date tool private?
Yes. It runs entirely in your browser, so dates, schedules, and notes are not uploaded or stored.
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