Calculer

Calculer

Defaults to today if cleared in some UIs; seed default is review date.

Updates as you type

Résultat

La formule

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.

Days = (TargetDate − FromDate) in civil days

Exemple détaillé

  1. From 2026-07-22 to 2026-12-25
  2. Civil-day gap = 156 days
  3. 156 = 22 weeks + 2 days · ≈ 5.1 months

Résultat: 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.

Faits intéressants

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.

Questions fréquentes

Mettez cette date en cible (depuis = aujourd'hui).

Affichage « il y a N jours ».

Oui — remplissez la date de départ optionnelle.

Ici la direction vers une cible compte.

Références

  1. ISO 8601 — ISO Calendar date representation.
  2. Time FAQs (leap years) — NIST Gregorian leap rules.