Enter a date from a letter, a parish register or a diary. We read it the way it was written at the time, then show the weekday, the same day in the other calendar and its Julian Day Number.
14 September 1752 · as written in Great Britain and its colonies
Thursday
Britain’s first Gregorian day. The day before was Wednesday 2 September 1752 (Julian), so 3–13 September 1752 never happened there.
The Julian calendar adds a leap day every fourth year, so its average year is 365¼ days, slightly longer than the year of the seasons. Over the centuries the dates slipped, and in 1582 Pope Gregory XIII's reform dropped ten days and changed the rule: century years are leap years only when they divide by 400, so 1700, 1800 and 1900 were not, but 2000 was.
Countries changed at different times. Britain and its colonies waited until 1752, when Wednesday 2 September was followed by Thursday 14 September. The weekdays carried on as normal; only the dates jumped. Russia changed in 1918 and Greece in 1923. The Julian–Gregorian converter has the full table.
Until 1752 the legal year in England began on 25 March, so a date between 1 January and 24 March carried the previous year's number. Writers often gave both: 1 February 1720/21 is 1 February 1721 as we count today. This finder reads every year as starting on 1 January and tells you when a date falls in that window; the converter has a box for years copied straight from an Old Style document.
Astronomers number days in one unbroken count from noon on 1 January 4713 BCE (in the Julian calendar), ignoring months and years. Each day has one number, whichever calendar a writer used, which makes it the safest way to compare dates. Every conversion on this site goes through it.
Every tool names its sources.
Old Style to New Style and back, with every country's switch date and the 10 to 13 days between them.
Western and Orthodox Easter for any year, with Ash Wednesday, Good Friday, Ascension and Pentecost.
Numbers and whole dates in Roman numerals and back, with older forms like IIII and MDCCCC explained.
Events with BCE and CE dates, notes and era bands, scaled for you; print it or save it as SVG or PNG.
Pounds, shillings and pence to decimal at the 1971 rate and back, with guineas, crowns and florins.
Two free services for researching online.
Record indexes, archive newsletters and free downloads often want an email address first. CleanTempMail gives you a free temporary inbox at once, with no sign-up, a random or custom address on hundreds of domains, and messages deleted automatically after 3 days.
Collect the one-off link; keep your own inbox for the archives you trust.
Open a temporary inboxFollowing a link to an unfamiliar transcription site, scanned book or auction listing? WebTraceCheck's disposable cloud browser opens it on an isolated desktop that is deleted after each session, and its free DNS and domain lookup shows the details behind a site's domain.
Nothing to install, with free time every day.
Try WebTraceCheckBecause that country skipped it. When a country moved to the Gregorian calendar it left out the dates in between: in Britain, 3 to 13 September 1752 never happened. The card also shows the weekday if your source used the other calendar, in case the date was written Julian or Gregorian after all.
Choose the country your document comes from to read the date as it was written there. Choose the Julian or Gregorian calendar if you already know which one the writer used, for example a date marked O.S. (Old Style) or N.S. (New Style).
No. Only the dates jumped: Wednesday 2 September was followed by Thursday 14 September, so the weekly cycle ran on unbroken. That is why a weekday written in a document can help show which calendar the writer was using.
Neither used the Julian calendar. Japan moved from its lunisolar calendar to the Gregorian on 1 January 1873, and a Turkish law of 1925 made the international year count official from 1 January 1926. Dates in their older calendars are not converted here.