Days Until Calculator
Pick a target date (and optional “from” date) to see days remaining, whole weeks, and a rough months estimate. Past dates show how many days ago.
Calculate
Calculate
Result
The formula
Normalize both dates to local midnight, then days = round((target − from) / 86,400,000). Positive means upcoming; negative means past; zero means today. Weeks = floor(|days|/7); months ≈ |days|/30.4375.
Worked example
- From 2026-07-22 to 2026-12-25
- Civil-day gap = 156 days
- 156 = 22 weeks + 2 days · ≈ 5.1 months
Result: 156 days until Dec 25, 2026
How the countdown is counted
This is a one-sided date span: “how long until X?” rather than an unordered difference between two arbitrary dates.
Default “from” date
If From is empty, we use today in your browser’s local timezone. Both dates are treated as midnights — time of day is ignored.
Past dates
If the target is before the from date, we show “N days ago” with a past-date badge instead of a negative countdown.
Vs date difference
Date difference always returns a positive span between two dates. Days-until preserves direction (upcoming vs past) and highlights a single target.
Interesting facts
Civil days
We count calendar midnights crossed — weekends and holidays included.
Months are approximate
Month length varies; the ≈ months figure uses 30.4375 days (365.25/12).
Leap days count
February 29 between the dates adds one day automatically.
Time zones
Local midnight matters near zone boundaries — agree on a shared calendar date for events.
Business days
This tool does not skip weekends or holidays.
Frequently asked questions
Set the target to Dec 25 of your year (and leave From blank for today). The result shows days remaining.
You will see “N days ago” instead of a forward countdown.
Yes — fill the optional From date (e.g. project kickoff).
Date difference is an absolute span. Days-until answers “how long until/since this target?” with direction.
Set the target date to January 1 of the year you want and leave From blank to count from today. The result shows exact days remaining, whole weeks, and an approximate months figure.
Yes — set the target to this year’s occurrence. Once that date passes, update the target to next year’s date to restart the countdown.
Both dates are treated as local midnights in your browser’s time zone, with no time-of-day component. Near a time zone boundary at midnight, the exact day shown can shift by one depending on which zone is used.
References
- ISO 8601 Calendar date representation.
- Time FAQs (leap years) Gregorian leap rules.