How Swedish compounds work
Swedish builds new words by joining old ones, and it writes the result as one word. A sjukförsäkringsavgift is a fee (avgift) for health insurance (sjukförsäkring), which in turn is insurance (försäkring) for when you are ill (sjuk). Read a compound from the end: the last part says what the thing is, and everything before it narrows it down.
| Compound | Parts | Literally | Meaning |
|---|---|---|---|
| kaffekopp | kaffe + kopp | coffee cup | coffee cup |
| barnvagn | barn + vagn | child carriage | pram, stroller |
| sjuksköterska | sjuk + sköterska | sick carer | nurse |
| solsken | sol + sken | sun shine | sunshine |
| glasögon | glas + ögon | glass eyes | glasses |
| kvällstidning | kväll + s + tidning | evening paper | tabloid |
The linking letters
Between the parts there is sometimes an extra letter that belongs to neither word. Swedish grammar calls it a fogebokstav, a joining letter. The splitter marks it in colour.
| What happens | Examples |
|---|---|
| Nothing: the words just meet | ölglas, barnvagn, solsken, kaffekopp |
| A linking -s- | fotbollsplan, kvällsmat, lördagskväll, arbetsgivare |
| The first word drops its final -a | stjärna → stjärnhimmel, flicka → flickvän, skriva → skrivbord |
| The first word drops its final -e | pojke → pojkvän, arbete → arbetsgivare |
| An old -o- or -u- in place of -a | kyrka → kyrkogård, vecka → veckotidning, gata → gatukök |
| A plural as the first part | öga → ögonblick, ögonläkare; öra → öronläkare |
| An old -e- | rättegång (a trial) |
Whether a word takes the -s- is mostly a matter of the first part, and there are useful rules of thumb. A first part that is itself a compound usually does take it: vägkarta but järnvägskarta, bankbok but sparbanksbok. First parts that end in -ande, -ende, -else or an s-sound usually don't: sjukhusvård, inkallelseorder. When in doubt, Svenska Akademiens ordlista (SAOL) has the common compounds.
One spelling rule changes what you see: when three identical consonants would meet, only two are written. Natt + tåg is written nattåg, and the splitter puts the missing letter back when it names the parts. All three come back when the word is broken across two lines (natt-tåg), and Språkrådet allows a hyphen where the short form would be hard to read: glas-skål or glass-skål.
Writing compounds yourself
Swedish compounds are written as one word. Splitting them in two, särskrivning, is a mistake Swedes notice at once, and spell checkers trained on English often push you towards it. If you say the word with one stress and no pause, it is a compound and you write it together. With three or more parts, add an -s- before the last part in most cases (järn + väg + karta → järnvägskarta), and use a hyphen when one part is an abbreviation, a number or a name written in several words: e-post, 12-tiden, Zara Larsson-låt.
The rules above follow Språkrådet's Snabba skrivregler (Institutet för språk och folkminnen, chapter 3) and Myndigheternas skrivregler (Ds 2001:32, section 3.1). Last checked 7 October 2026.
How the splitter works
It tries every way of cutting the word into dictionary words, allowing the linking letters and stem changes above, and scores each cut: every extra part costs something, so fewer and longer parts win, and rare words cost more than common ones. The last part may be inflected, so kyrkogårdarna works as well as kyrkogård. Where Wiktionary or Folkets lexikon already record where a compound's parts meet, the splitter follows them.
Reading a whole text? The Swedish reader lets you tap any word for its meaning and uses this splitter for compounds it doesn't know. To check a noun's gender on its own, use En or ett?, and for a word's full entry, the dictionary.
Word data: Wiktionary via kaikki.org (CC BY-SA 4.0), Folkets lexikon (CC BY-SA 2.5) and word frequencies from OpenSubtitles by Hermit Dave (CC BY-SA 4.0).
Frequently asked questions
Why are Swedish words so long?
Because Swedish writes compounds as one word. Where English puts words side by side (health insurance fee), Swedish joins them: sjukförsäkringsavgift. The words themselves are usually short and common; once you can see the joins, a long word is just a short phrase.
What is the s in the middle of words like fotbollsplan?
A linking letter, in Swedish fogemorfem or foge-s. Many first parts take an -s- before the next part: fotboll + s + plan, kväll + s + mat. It means nothing on its own. A few older compounds have a vowel instead: kyrkogård, gatukök, veckotidning.
Is a compound en or ett?
It takes the gender of its last part. Ett glas gives ett ölglas; en plan (a pitch) gives en fotbollsplan. The splitter shows the gender of the last part, so it can answer for compounds no dictionary lists.
Can I write Swedish compounds as two words?
No. Writing a compound apart (särskrivning) is one of the most noticed mistakes in Swedish, and it can change the meaning. The classic example: a sjuksköterska is a nurse, but a sjuk sköterska is a nurse who is ill herself.
Does the splitter always get it right?
Not always. A few words can be cut in two honest ways (fotbollslag is a football team, but fotboll + slag would be a football blow), and some old compounds have drifted from their parts. On a test of more than 2,000 compounds whose parts Wiktionary or Folkets lexikon record, the scoring alone finds the recorded joins about 96 times in 100; where the dictionaries know the joins, it uses them.
Does the word I type leave my browser?
No. The page downloads the word list once and does the splitting on your own device. Nothing you type is sent to us.