Punctuation and Number Formatting

Two texts can be spelled identically and still look "foreign" because of how the numbers, dates, and quotation marks are formatted. Icelandic follows continental-European conventions, several of which are the exact reverse of English: the decimal point becomes a comma, the thousands comma becomes a period (or a space), quotation marks sit low-then-high, the clock is 24-hour, and a date puts the day first with the month in lowercase. None of these is hard, but each is a place where an English speaker's automatic habit produces something a native reader registers as wrong. This page covers the formatting conventions; sentence-level syntax and clause punctuation belong with the syntax pages.

Decimal comma, period (or space) for thousands

The most important switch: Icelandic uses a comma as the decimal separator and a period (or a thin space) as the thousands separator — the opposite of English. So English 3.14 is Icelandic 3,14, and English 1,000 is Icelandic 1.000 (or 1 000 with a space). Get these two backwards and a price or measurement reads as nonsense.

Money: amount + kr.

Prices are written with the amount (using the period/space thousands separator) followed by kr. — the abbreviation for krónur. The kr. normally comes after the number, with a space: 1.250 kr. There is no decimal part in everyday krónur prices, since the eyrir subunit is long defunct, so you rarely see a decimal comma in a price — but you will see the period thousands separator constantly.

The 24-hour clock and kl.

Time is given on the 24-hour clock, and the abbreviation kl. (klukkan, "the clock/o'clock") introduces it. The separator between hours and minutes is a colon (or sometimes a period): kl. 14:30 "at 2:30 p.m." There is no a.m./p.m.; fjórtán þrjátíu (fourteen thirty) is simply the time. In running speech people also say half-hours the German way (hálf þrjú = "half three" = 2:30), but in writing, the digital 24-hour form dominates.

Dates: day first, lowercase month, ordinal period

A written date puts the day first, then the month, then the year: 5. júní 2026. Three things follow from this that surprise English speakers:

1. The day is an ordinal, written as a numeral followed by a period: 5. means fimmti ("fifth"). That period is not a sentence-ending full stop — it is the ordinal marker (see the next section).
2. The month is lowercase: júní, mars, desember — Icelandic does not capitalise month names (or weekday names).
3. There is no comma before the year:
   5. júní 2026
   , not
   5. júní, 2026
   .

The big trap: a period after a numeral = ORDINAL

This deserves its own section because it genuinely confuses English readers. In Icelandic, a period written directly after a numeral turns it into an ordinal. 5 is "five"; 5. is "fifth." 3 is "three"; 3. is "third." So 5. júní is "the 5th of June," and 2. hæð is "the 2nd floor," and í 1. sæti is "in 1st place." An English reader sees 5. júní and parses the period as a full stop — "5. End of sentence. Then 'júní'?" — which is completely wrong. The period belongs to the number, marking it ordinal.

Quotation marks: „low–high"

Formal Icelandic print uses low-then-high quotation marks: an opening mark on the baseline („) and a closing mark raised (“) — the German style, „…“. So a quoted sentence looks like „Komdu hingað,“ sagði hún ("'Come here,' she said"). In everyday digital writing — texts, emails, social media — people very often use plain straight quotes ("…") out of convenience and keyboard limitations, and that is widely accepted online. But in books, newspapers, and formal documents, the „ “ pair is the standard, and English-style high-opening quotation marks (“…”) look out of place.

Comma usage is lighter than German (and varies from English)

Icelandic punctuates commas more lightly than German and somewhat differently from English. Modern Icelandic largely uses the meaning-based (rather than strictly grammatical) comma: you set off clauses and items for clarity and breath, but you do not mechanically put a comma before every subordinate clause the way German does. In practice this means fewer commas than a German learner expects, and a distribution close to — but not identical with — English. The detailed rules belong to a syntax page; for formatting, just don't over-comma in the German manner.

How this differs from English

The pattern is consistent: where English and Icelandic differ, Icelandic follows the continental-European convention. Decimal comma vs English point; thousands period/space vs English comma; 24-hour clock vs 12-hour a.m./p.m.; day-first, lowercase-month dates vs English month-first (or comma'd) dates with capital months; „ “ quotation marks vs English “ ”. The one that actively causes misreadings — not just an accent but a real comprehension error — is the ordinal period: an English speaker reads 5. júní as a broken sentence, when it simply means "the 5th of June."

Common Mistakes

This is the headline numeric error. Swap both separators when writing in Icelandic.

Capitalising the month is a direct English transfer error; Icelandic months and weekdays are lowercase.

The ordinal period is the comprehension trap. A period on a numeral means "-th," not "end of sentence."

In books and formal documents, use „ “. Straight quotes are fine online but not in formal print.

Key Takeaways

• Decimal = comma (3,14); thousands = period or thin space (1.000 / 1 000) — the reverse of English.
• Money: amount + kr. after a space (590 kr., 12.500 kr.).
• Time: 24-hour clock with kl. and a colon (kl. 14:30); no a.m./p.m.
• Dates: day-first, ordinal day with a period, lowercase month, no comma before the year (
  5. júní 2026
  ).
• A period after a numeral marks an ORDINAL (5. = "5th,"
  2. hæð
  = "2nd floor") — not a sentence-ending stop. This is the chief comprehension trap.
• Quotation marks: formal print uses „ “ (low–high); straight quotes are normal in casual online writing.
• Commas are used more lightly than in German; don't over-comma.