World Calendars
French Republican date today
The calendar of the French Revolution, used in France from 1793 until the end of 1805. It replaced the week with ten-day weeks and named the months after the seasons.
20 Brumaire an CCXXXV
Décadi, year 235
- In the Gregorian calendar
- Wednesday 11 November 2026
- This day began
- At midnight, as Wednesday 11 November 2026 begins
- This day ends
- At midnight, as Thursday 12 November 2026 begins
- Reformed (Romme) rule
- 21 Brumaire an CCXXXV
- Year Year 235 began
- Wednesday 23 September 2026
- Next new year
- Thursday 23 September 2027 (in 316 days)
- This year has
- 365 days
- Year 1 began
- 22 September 1792
- How it works
- 12 months of 30 days, then 5 or 6 festival days to end the year
- Years count from
- 22 September 1792, the day France was proclaimed a republic
- New year
- On the day of the autumn equinox in Paris
- Ended
- 1 January 1806, when the usual calendar returned; briefly revived in Paris in 1871
Next holidays in this calendar
316 days
French Republican New Year 1 Vendémiaire an CCXXXVI
23 September 2027 · French Republican
How the French Republican calendar works
The year has 12 months of 30 days. Each month is split into three décades of 10 days, which took the place of the week. Its days are named by number, from primidi and duodi to décadi, the tenth day, which replaced Sunday as the rest day. Fabre d'Églantine invented the month names, with endings that rhyme by season.
| No. | Month | Meaning | Days |
|---|---|---|---|
| 1 | Vendémiaire | vintage (autumn) | 30 |
| 2 | Brumaire | mist (autumn) | 30 |
| 3 | Frimaire | frost (autumn) | 30 |
| 4 | Nivôse | snow (winter) | 30 |
| 5 | Pluviôse | rain (winter) | 30 |
| 6 | Ventôse | wind (winter) | 30 |
| 7 | Germinal | seedtime (spring) | 30 |
| 8 | Floréal | blossom (spring) | 30 |
| 9 | Prairial | meadow (spring) | 30 |
| 10 | Messidor | harvest (summer) | 30 |
| 11 | Thermidor | heat (summer) | 30 |
| 12 | Fructidor | fruits (summer) | 30 |
| - | Sansculottides (complementary days) | festivals | 5 or 6 |
The days after Fructidor, first called the sansculottides and from year III (1795) the jours complémentaires, are festivals of Virtue, Talent, Labour, Convictions and Honours, plus the Revolution in a leap year, which was called sextile after that sixth day. In place of saints' days, every quintidi was named after an animal, every décadi after a farm tool, and the days of Nivôse after minerals.
Variants and the method used here
The decree says: "Each year begins at midnight, with the day on which the true autumnal equinox falls for the Paris Observatory." It also made every fourth year sextile, and the two rules conflict, because the equinox does not keep a strict four-year rhythm. Years III, VII and XI were leap years, and XV and XX were planned, five years apart.
Delambre devised a fixed rule, which Gilbert Romme presented on 19 Floréal an III (8 May 1795): Gregorian leap years applied to Republican years (IV, VIII, XII and so on), with year 4000 a common year. It was never adopted.
This site shows both. The main date follows the equinox rule: the September equinox comes from astronomy-engine, an open-source astronomy library, converted to true solar time on the Paris Observatory meridian. This reproduces the leap years III, VII and XI. The second line applies Romme's rule from year I, so it differs from the dates in use before 1806, and from the equinox in some modern years: year 235 began on 23 September 2026 by the equinox and on 22 September by Romme's rule. Year starts are precomputed for 1792 to 2400, so the converter gives no date before 22 September 1792 or after the end of 2400.
A short history
A commission led by Gilbert Romme, with the mathematicians Lagrange and Monge among its contributors, drew up the calendar. It was presented to the National Convention on 23 September 1793, adopted in October 1793 and dated back to 22 September 1792, the day the Convention proclaimed France a republic. A decimal clock of 10 hours a day came with it; its compulsory use was suspended on 7 April 1795.
The Concordat of 1801 brought back Sunday rest and the Gregorian weekday names from 18 April 1802. An act dated 22 Fructidor an XIII (9 September 1805) abolished the calendar, citing its leap years, which depended on the sun's uneven motion, and its epoch and new year, tied to a French event in autumn. The Gregorian calendar returned on 1 January 1806. The Paris Commune used the Republican calendar again in its Journal officiel from 6 to 23 May 1871.
Sources
How this site calculates the date: Equinox rule of 1793: each year begins on the day of the autumn equinox in Paris true solar time. The reformed Romme rule, applied from year I, is shown alongside.