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What week is it

The ISO or US week number of today or any date, and the days the week runs from and to. Free, with no account or uploads.

Find the week number

The ISO week is shown, which starts on Monday; the US way is under More options.

Dates follow the Gregorian calendar back to year 1, as computers do; before 1582 (1752 in Britain and its colonies) records were kept in the Julian calendar, so old dates may differ from what was written at the time.

How it works and help
Worked out in your browser. Nothing you type is sent anywhere; a country's holidays are read from this site's own files.

A little help along the way

Follow these steps. Every option is explained underneath. Everything runs in your browser; nothing is sent anywhere.

  1. Say what you want to knowHow long between two dates is the usual. The others count down to an event, work out an age, move a date, count working days or give a week number.
  2. Choose the datesToday is filled in. Change either date, or type an event such as Christmas or my birthday 14 March.
  3. Read the answerIt comes first in words, then in days and weeks, with the rule it followed under it.
  4. Keep itCopy the answer, add a day to your calendar, or copy a link that carries the date.

Questions people ask

Which week numbering is this?
ISO 8601: weeks start on Monday and week 1 holds the year's first Thursday. The US way, from Sunday, is under More options.
Why is 1 January in week 52 or 53?
Under ISO rules the first days of January belong to the previous year's last week when that week holds most of them.
Can I find the week of another date?
Yes. Change the date and the week number, its Monday and its Sunday are worked out for that day.

This page is the Date calculator, opened for this one job; every other tool it has is one press away. Each of its settings is explained on the Date calculator's own page.

Read the step-by-step guide

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