A relative clause modifies a noun by attaching a small clause to it: the man who lives here, the book that I bought. Finnish builds these with two relative pronouns — joka and mikä — and the choice between them is grammar, not style. This page treats the relative clause as a construction: where it sits, why the comma is obligatory, how joka juggles two kinds of agreement at once, and when mikä must take over. The full pronoun paradigms live on the joka and mikä pages; here the focus is the clause itself.
Shape of the construction
A Finnish relative clause comes right after its antecedent (the noun it describes), opens with the relative pronoun, and is set off by a comma. Word order inside is ordinary — subject, verb, the rest — with no inversion.
Mies, joka asuu tässä talossa, on lääkäri.
The man who lives in this house is a doctor.
Ostin kengät, jotka olivat alennuksessa.
I bought the shoes that were on sale.
The comma is not optional. Unlike English, which uses commas to distinguish "my father, who lives here" from "the man who lives here", Finnish puts a comma before every relative pronoun, restrictive or not. This means the split between joka and mikä is about the antecedent type, not about restrictive versus non-restrictive — a distinction Finnish punctuation simply does not mark.
joka: for a specific noun antecedent
Use joka when the thing you are describing is an ordinary, concrete noun — a person, an object, a place. Now comes the key mechanic. Joka answers to two nouns at once, in two different ways:
- Its number comes from the antecedent. A plural antecedent forces the plural jotka.
- Its case comes from its own role inside the relative clause — completely independent of how the antecedent is used in the main clause.
So the antecedent noun and the relative pronoun can stand in totally different cases, even though they refer to the same thing. Here is a single antecedent (kirja, always the thing being talked about) with the pronoun in four different cases as its in-clause job changes:
| Relative clause | joka form | Its job in the clause |
|---|---|---|
| kirja, joka on pöydällä | joka (nom.) | subject — "which is on the table" |
| kirja, jonka ostin | jonka (gen.) | total object — "which I bought" |
| kirja, jota luin eilen | jota (part.) | partial object — "which I was reading" |
| kirja, jossa on kuvia | jossa (iness.) | "in which there are pictures" |
Kirja, jonka ostin eilen, oli todella kallis.
The book (that) I bought yesterday was really expensive.
Talo, jossa asun, on yli sata vuotta vanha.
The house I live in is over a hundred years old.
Nainen, jolle annoin avaimet, on naapurini.
The woman I gave the keys to is my neighbour.
In jonka ostin, the pronoun is the object of ostin → the genitive-shaped object form jonka. In jossa asun, asua governs the inessive → jossa "in which". In jolle annoin, antaa jollekin pulls the pronoun into the allative → jolle "to whom". The antecedents kirja, talo, nainen meanwhile sit in whatever case the main clause needs. Two nouns, two cases, one referent.
Number is the easy half: a plural antecedent forces plural jotka / joita / joissa … whatever the case.
Ihmiset, jotka odottavat bussia, ovat aivan märkiä.
The people who are waiting for the bus are soaking wet.
Elokuvat, joista puhuimme, ovat nyt suoratoistopalvelussa.
The films we talked about are now on the streaming service.
mikä: for a clause, a pronoun or a superlative
mikä takes over from joka in three situations where there is no ordinary noun to point at:
- A whole clause / idea. When "which" refers back to the entire preceding statement — "the fact that …" — Finnish uses mikä, never joka.
- A pronominal antecedent — se "that (thing)", kaikki "everything", jokin "something", mikään "anything", jokainen "each".
- A superlative or a limiter like ainoa "only", ensimmäinen "first", viimeinen "last".
Hän myöhästyi junasta, mikä ärsytti kaikkia.
He missed the train, which annoyed everyone. (refers to the whole fact → mikä)
Kaikki, mikä kiiltää, ei ole kultaa.
All that glitters is not gold. (pronoun antecedent kaikki → mikä)
Se oli paras kirja, minkä olen koskaan lukenut.
It was the best book I've ever read. (superlative → mikä)
Like joka, mikä still takes its case from its own clause: in kaikki, minkä näen the pronoun is the total object of näen → minkä; in kaikki, mitä tiedän the verb governs a partitive → mitä. The choice of mikä over joka is about the antecedent; the choice of minkä versus mitä is the ordinary object-case question.
The minimal contrast
Change only the antecedent and watch the relative pronoun flip:
| Sentence | Why |
|---|---|
| Hän voitti kilpailun, jonka kaikki muistavat. | antecedent = the noun kilpailu → joka |
| Hän voitti kilpailun, mikä yllätti kaikki. | antecedent = the whole fact "that he won" → mikä |
Hän voitti kilpailun, jonka kaikki muistavat vieläkin.
He won the competition, which everyone still remembers. (joka = the competition)
Hän voitti kilpailun, mikä yllätti kaikki.
He won the competition, which surprised everyone. (mikä = the fact that he won)
Same English "which", two different Finnish pronouns, because the antecedent is a noun in the first and a whole proposition in the second. When you are unsure at the boundary, the dedicated joka vs mikä page works through the grey cases.
Comparison with English
English relative pronouns barely inflect ("who / whom / which / that") and lean on word order and stranded prepositions — "the house that I live in". Finnish loads all of that onto the pronoun: the case marks the role, so there are no stranded prepositions and no special word order. The price is that you must case the pronoun every time, and the case comes from the inner clause. English also collapses joka and mikä into a single "which/that", so the antecedent-driven split has to be learned from scratch — especially the clause-referring mikä, where English "which" after a comma must become mikä, never joka.
Common Mistakes
❌ Kirja, joka ostin, oli kallis.
Incorrect — the pronoun is the object of ostin, so it must be the genitive object jonka, not the subject-form joka.
✅ Kirja, jonka ostin, oli kallis.
The book that I bought was expensive.
❌ Ihmiset, joka odottavat, ovat märkiä.
Incorrect — a plural antecedent (ihmiset) forces the plural jotka.
✅ Ihmiset, jotka odottavat, ovat märkiä.
The people who are waiting are wet.
❌ Hän voitti, joka yllätti kaikki.
Incorrect — 'which' refers to the whole fact, so it must be mikä, not joka.
✅ Hän voitti, mikä yllätti kaikki.
He won, which surprised everyone.
❌ Se on ainoa ravintola joka on auki.
Incorrect — a comma is required before the relative pronoun.
✅ Se on ainoa ravintola, joka on auki.
It's the only restaurant that's open.
❌ Kaikki, joka kiiltää, ei ole kultaa.
Incorrect — the pronoun antecedent kaikki takes mikä, not joka.
✅ Kaikki, mikä kiiltää, ei ole kultaa.
All that glitters is not gold.
Key Takeaways
- A relative clause comes right after its antecedent, with a comma before the pronoun (both sides if it is embedded).
- joka is for a specific noun antecedent; its case comes from its role in the clause (jonka object/possessor, jossa "in which", jolle "to whom") and its number from the antecedent (jotka).
- jonka is the genitive — the object or possessor form — never a subject.
- mikä takes over for a whole clause, a pronoun antecedent (se, kaikki, jokin…), or a superlative/limiter; it too takes its case from its own clause (minkä, mitä).
- The joka/mikä split is about antecedent type, not restrictive versus non-restrictive — Finnish punctuation makes no such distinction.
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Start learning Finnish→Related Topics
- The Relative Pronoun jokaB1 — joka links a relative clause to a specific noun — agreeing with it in number but taking the case its own clause demands (jonka, jota, jossa, jolle).
- Relative mikä and Its UsesB2 — When the antecedent is a whole clause, a pronoun like se or kaikki, or a superlative, the relative is mikä — not joka. The rule and its cases.
- joka vs mikä (Relative)B1 — Choosing the relative pronoun: joka points back to a specific noun antecedent, while mikä points back to a whole clause, an indefinite or superlative head, or the pronoun se.
- että-Clauses in DepthB1 — The finite että complement clause in depth: which verbs take it, why Finnish keeps the original tense, and the se että 'the fact that' pattern.