How you write numbers and dates in Czech differs sharply — and consistently — from English and especially American habits. The decimal point and the comma swap jobs; thousands are split by a space; dates run day-month-year; a lone period after a number turns it into an ordinal; and money comes after the amount. None of this is decorative. Write 3.14 for pi or 1,000 for a thousand and a Czech reader will misparse you instantly: to them 3.14 looks like a date fragment and 1,000 looks like the number one with a decimal tail. This page covers the written conventions; the ordinals pages handle how to actually say and decline these numbers.
Decimals: a comma, not a point
Czech uses a comma as the decimal separator. The point is not used for decimals at all.
| Czech writes | Read aloud | English would write |
|---|---|---|
| 3,14 | tři celé čtrnáct | 3.14 |
| 1,5 litru | jedna celá pět litru | 1.5 litres |
| 19,99 Kč | devatenáct korun devadesát devět | 19.99 CZK |
The whole part is connected to the fraction by the word celá / celé ("whole"): jedna celá pět (1,5), tři celé čtrnáct (3,14). This celá is exactly where the comma sits on the page.
To mléko má jenom 1,5 % tuku.
That milk has only 1.5% fat. (decimal comma: jedna celá pět procenta)
Maraton měří 42,195 kilometru.
A marathon is 42.195 kilometres long. (the comma is the decimal point here)
Ta káva stojí 49,90 Kč.
That coffee costs 49.90 crowns. (49,90 with a comma, currency after)
Thousands: a space, never a comma
Large numbers are grouped in threes by a space — ideally a thin, non-breaking space — and never by a comma. The comma is busy being the decimal point.
| Czech writes | English would write |
|---|---|
| 1 000 | 1,000 |
| 25 000 | 25,000 |
| 1 000 000 | 1,000,000 |
A four-digit figure can be written either way — 1000 or 1 000 — but from five digits up the grouping space is standard.
Na koncert přišlo přes 10 000 lidí.
More than 10,000 people came to the concert. (space, not comma)
Ten byt stál skoro 6 000 000 korun.
That flat cost almost 6,000,000 crowns. (each group of three split by a space)
Dates: day, then month, then year
Czech dates run day → month → year, the reverse of the American month-first order. In figures, each number is followed by a period (it's an ordinal) and the three parts are separated by spaces: 24. 12. 2024.
Schůze je naplánovaná na 24. 12. 2024.
The meeting is scheduled for 24 December 2024. (day. month. year, with spaces)
You'll also see the compact form 24.12.2024 without spaces, common in (informal) writing and on forms; the spaced version is the (formal) typographic norm.
When the month is spelled out, the day stays an ordinal (with its period) and the month goes into the genitive case — literally "the 24th of December":
Přijdu 1. března, tak na mě nezapomeň.
I'll come on the 1st of March, so don't forget me. (1. března = ordinal day + genitive month)
Druhá světová válka skončila 8. května 1945.
World War II ended on 8 May 1945. (8. května — ordinal + genitive)
The detailed declension of these forms lives on the dates ordinals page.
The ordinal period: a number meaning "-th"
A period directly after a number marks it as an ordinal — the written equivalent of English -st, -nd, -th. So 5. means "fifth," 3. means "third." This is why dates carry periods, and it shows up everywhere else too.
Bydlíme ve 3. patře, výtah je vlevo.
We live on the 3rd floor, the lift is on the left. (3. = třetím)
Náš syn chodí do 2. třídy.
Our son is in the 2nd grade. (2. = druhé)
Doběhla na krásném 1. místě.
She finished in a wonderful 1st place. (1. = prvním)
Roman numerals naming rulers also take this period: Karel IV. (Charles the Fourth), Karel čtvrtý.
Time: the 24-hour clock
Official and written times use the 24-hour clock, with hours and minutes split by a period or a colon: 14.30 or 14:30.
Sejdeme se ve 14.30 přímo před kinem.
We'll meet at 2:30 p.m. right in front of the cinema. (14.30 — 24-hour clock)
Vlak odjíždí v 8:15 z prvního nástupiště.
The train leaves at 8:15 from platform one. (8:15)
In everyday speech, Czechs often switch to the (informal) "quarter/half" system instead — čtvrt na devět (8:15, literally "a quarter onto nine") or půl třetí (2:30, "half of three"). That spoken system has its own telling-time page; in writing, the digital 24-hour form is safest.
Currency: amount first, then Kč
The currency follows the amount, with a space: 100 Kč, 19,99 Kč, 250 EUR. The symbol or code never leads the way the dollar sign does in English.
Vstupné je 150 Kč pro dospělé a 80 Kč pro děti.
Admission is 150 crowns for adults and 80 crowns for children. (amount, then Kč)
Common Mistakes
These are pure transfer errors from English/US conventions — the most common writing mistakes English speakers make in Czech.
❌ Pí je přibližně 3.14.
Incorrect — Czech uses a comma for decimals, not a point.
✅ Pí je přibližně 3,14.
Pi is approximately 3.14.
❌ Ve městě žije přes 1,000,000 lidí.
Incorrect — thousands are grouped with a space, never a comma.
✅ Ve městě žije přes 1 000 000 lidí.
Over a million people live in the city.
❌ Narodil se 12/24/1990.
Incorrect — Czech dates are day-month-year, not the US month-first order.
✅ Narodil se 24. 12. 1990.
He was born on 24 December 1990.
❌ Bydlím v 5 patře.
Incorrect — the ordinal needs its period: 5. patro means 'fifth floor'.
✅ Bydlím v 5. patře.
I live on the 5th floor.
❌ Lístek stojí Kč 200.
Incorrect — the currency follows the amount in Czech.
✅ Lístek stojí 200 Kč.
The ticket costs 200 crowns.
Key Takeaways
- Decimal = comma (3,14); thousands = space (1 000 000). English does the reverse — flip both.
- Dates run day. month. year (
- 2024
- prosince 2024
- A period after a number makes it an ordinal (
- patro
- třída
- Written time uses the 24-hour clock (14.30 / 14:30); the "quarter/half" system is spoken.
- Currency follows the amount (200 Kč).
Now practice Czech
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Start learning Czech→Related Topics
- DatesA2 — Saying and writing dates with the genitive ordinal: prvního ledna, in years and the day-month genitive.
- Ordinal NumbersA2 — první, druhý, třetí … — how Czech ordinals decline like adjectives, how compound ordinals are built, and the digit-plus-period notation.
- Money and CurrencyA2 — koruna/koruny/korun and haléř agreement, prices, and reading sums of money.
- Telling the TimeA2 — Hodin/hodiny agreement, half/quarter expressions (půl, čtvrt), and the 24-hour system.