Is this D-day counter free?

Yes, completely free — no subscription, no account, no hidden fees.

Do you upload my event data to a server?

No. All event data is stored only in your browser's localStorage and never sent anywhere. Your dates stay on your device.

Does it work offline?

Yes. The tool runs entirely in your browser with no server calls, so it works even without an internet connection.

How many events can I track at once?

There is no hard limit — add as many events as you need. They are automatically sorted so the nearest date always appears first.

Will my events disappear if I close the browser?

No. Events are saved in localStorage and persist across browser sessions until you explicitly delete them.

Does the count treat today as day zero?

Yes. The tool subtracts one calendar date from the other, so today shows D-DAY, tomorrow shows D-1 and yesterday shows D+1. There is no extra offset. If your school or workplace counts the start date itself as day one, add one to the D+N figure. Because the gap is rounded to whole days, daylight-saving shifts never move a count by a day.

Is there a limit on the event name?

Event names are capped at 40 characters, which comfortably fits a label such as "Final exam - chemistry". The counter is built to show a whole list of events at a glance, so short names keep the list readable on a phone. Longer notes are better kept in a notes app; only the name and the date are stored here.

📅 D-Day Counter — Days Until or Since Any Date

This free D-day counter calculates how many days remain until — or have passed since — any date you choose, running 100% in your browser with no account or upload required.

Add event

Name

Date

Private by design. This tool runs entirely in your browser — nothing you enter is uploaded or stored, and it works offline.

About

Add as many named events as you like — deadlines, anniversaries, exam dates, countdowns to trips — and the tool instantly shows D-1, D-DAY, or D+N for each. Events are sorted by closeness to today and saved only in your browser's localStorage, so your data never leaves your device. Because there is no server involved, the counter works fully offline and keeps working even if your network drops.

How to use

Type a name for your event (e.g. "Project deadline") in the Name field.
Pick the target date using the Date picker.
Click ＋ Add (or press Enter) to save the event.
View D-day labels — D-N (days left), D-DAY (today), or D+N (days passed) — sorted by closeness to today.
Delete any event with the trash icon when you no longer need it.

FAQ

Is this D-day counter free?: Yes, completely free — no subscription, no account, no hidden fees.
Do you upload my event data to a server?: No. All event data is stored only in your browser's localStorage and never sent anywhere. Your dates stay on your device.
Does it work offline?: Yes. The tool runs entirely in your browser with no server calls, so it works even without an internet connection.
How many events can I track at once?: There is no hard limit — add as many events as you need. They are automatically sorted so the nearest date always appears first.
Will my events disappear if I close the browser?: No. Events are saved in localStorage and persist across browser sessions until you explicitly delete them.
Does the count treat today as day zero?: Yes. The tool subtracts one calendar date from the other, so today shows D-DAY, tomorrow shows D-1 and yesterday shows D+1. There is no extra offset. If your school or workplace counts the start date itself as day one, add one to the D+N figure. Because the gap is rounded to whole days, daylight-saving shifts never move a count by a day.
Is there a limit on the event name?: Event names are capped at 40 characters, which comfortably fits a label such as "Final exam - chemistry". The counter is built to show a whole list of events at a glance, so short names keep the list readable on a phone. Longer notes are better kept in a notes app; only the name and the date are stored here.