To ask a question about a person or a thing, Finnish uses an interrogative pronoun: kuka ("who"), mikä ("what, which"), kumpi ("which of two"), and millainen ("what kind of"). Two of them — kuka and mikä — inflect for case just like nouns, but on stems that look nothing like the nominative. The single most useful fact on this page is that "whose" is one word, kenen, and it comes from kuka even though it does not resemble it. Get the stems down and you can ask any question Finnish allows.
kuka — "who" (people)
Kuka asks about a person. Its trap is that only the nominative uses the ku- form; every other case is built on a completely different stem, kene-:
| Case | Form | Meaning |
|---|---|---|
| Nominative | kuka | who (subject) |
| Genitive | kenen | whose |
| Partitive | ketä | whom (partial/emotion object) |
| Accusative | kenet | whom (total object) |
| Inessive | kenessä | in whom |
| Adessive | kenellä | who has / on whom |
| Ablative | keneltä | from whom |
| Allative | kenelle | to whom |
Kuka tulee mukaan elokuviin?
Who's coming along to the movies?
Kenen takki tämä on? Se jäi eteiseen.
Whose coat is this? It was left in the hallway.
Kenelle sinä soitit äsken?
Who did you call just now? (to whom)
Notice kenen for "whose" — a single word doing the work of English "whose". Learners regularly reach for a two-word construction and produce nothing that works; the genitive kenen is the whole answer.
In casual speech the long forms often shorten: kenellä ~ kellä, kenelle ~ kelle, keneltä ~ keltä, keneen ~ kehen. Both are standard; the shorter ones are simply more colloquial. The plural of kuka is ketkä ("who", of several people): Ketkä tulevat? — but in practice singular kuka covers most questions.
mikä — "what / which" (things and selection)
Mikä asks about a thing, or picks one out of a set ("which"). Its oblique stem is mi-:
| Case | Form | Meaning |
|---|---|---|
| Nominative | mikä | what / which |
| Genitive | minkä | of what / which (as object too) |
| Partitive | mitä | what (partial object) |
| Inessive | missä | where (in what) |
| Elative | mistä | from where / about what |
| Illative | mihin | where to (into what) |
| Adessive | millä | with what / by what |
| Translative | miksi | why (into what) |
Mikä tämä on? En ole nähnyt tällaista ennen.
What is this? I've never seen anything like this before.
Mitä sinä teet tänä iltana?
What are you doing tonight?
Missä sä oot? Mä oon jo asemalla.
Where are you? I'm already at the station. (spoken)
Look at what falls out of this paradigm: the everyday "question adverbs" missä ("where"), mistä ("from where / about what"), mihin ("where to"), millä ("with what"), and miksi ("why") are literally the case forms of mikä. You are not learning separate words — you are declining one pronoun. That is a huge economy once you see it.
kuka or mikä? A quick word
The core split is simple: kuka for people, mikä for things and for picking from a set. English "what" spills over this line — "What's your name?" uses mikä in Finnish (Mikä sinun nimesi on?), but "Who came?" must be Kuka tuli?, never mikä. The full treatment of the gray areas lives on the kuka vs mikä page; here, just anchor the default.
Kuka tuli? — Naapuri tuli.
Who came? — The neighbour came.
kumpi — "which of two"
Kumpi is the pronoun English has no single word for: it means "which of exactly two". Whenever a choice is between two options, Finnish demands kumpi, not mikä. It inflects like a comparative adjective, on the stems kumpa- and kumma-:
| Case | Form |
|---|---|
| Nominative | kumpi |
| Genitive | kumman |
| Partitive | kumpaa |
| Inessive | kummassa |
| Illative | kumpaan |
| Adessive | kummalla |
Kumpi on parempi, tämä sininen vai tuo vihreä?
Which (of the two) is better, this blue one or that green one?
Kumman valitset — kahvin vai teen?
Which of the two do you choose — coffee or tea?
Kummassa kädessä se on?
In which hand (of the two) is it?
Note the frequent vai ("or", in questions offering a choice) alongside kumpi — the two go together naturally. From kumpi also come kumpikin ("both"), kumpikaan ("neither"), and jompikumpi ("either one"), which you will meet later.
millainen — "what kind of"
Millainen asks about quality or type. It inflects like a -nen adjective, on the stem millaise-, and agrees with its noun in case and number:
Millainen sää siellä on?
What kind of weather is it there?
Millaista ruokaa sinä haluaisit?
What kind of food would you like?
Millaisia ihmisiä siellä oli?
What kind of people were there?
The variant minkälainen means exactly the same thing and is at least as common in speech: Minkälainen auto sinulla on? = "What kind of car do you have?"
Comparison with English
Three things surprise English speakers here. First, "whose" is a case form, not a separate word — kenen, straight from kuka. Second, a whole family of English question words (where, where to, from where, with what, why) collapses into the cases of mikä: missä, mihin, mistä, millä, miksi. Learn one paradigm, get five question words free. Third, English has no word for kumpi: it says "which" whether there are two options or twenty, so learners default to mikä and never reach for kumpi even when Finnish requires it. If a question sets up exactly two choices — often flagged by vai — the pronoun must be kumpi.
Common Mistakes
❌ Mikä tuli ovelle?
Incorrect — a person as subject takes kuka, not mikä.
✅ Kuka tuli ovelle?
Who came to the door?
❌ Mikä on parempi, tämä vai tuo?
Incorrect — a choice between two demands kumpi.
✅ Kumpi on parempi, tämä vai tuo?
Which (of the two) is better, this or that?
❌ Kenen sinä näit eilen?
Incorrect — kenen is 'whose'; the object 'whom' is the accusative kenet (or partitive ketä).
✅ Kenet sinä näit eilen?
Whom did you see yesterday?
❌ Millainen se on väri?
Incorrect — millainen agrees with its noun in case and number: 'what colour' is millainen väri.
✅ Millainen väri se on?
What kind of colour is it?
Key Takeaways
- kuka = who (people); oblique stem kene-: kenen ("whose"), ketä/kenet (whom), kenelle ("to whom").
- mikä = what/which (things, selection); stem mi-: its cases missä, mistä, mihin, millä, miksi are the everyday question adverbs.
- kumpi = which of two (no English equivalent), inflected kumman, kumpaa, kumpaan; pairs with vai.
- millainen (= minkälainen) = what kind of; agrees with its noun in case and number.
- "Whose" is one word (kenen) and the object of kuka is the -t accusative kenet, never the genitive.
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Start learning Finnish→Related Topics
- mikä vs kukaA2 — Which question word to use: kuka asks who (a person's identity), mikä asks what or which (a thing, a kind, or a name) — plus their case forms and the trap of asking *Mikä hän on?
- Question Words: kuka, mikä, missä, milloin, miksiA1 — Finnish open questions use pro-words with no -ko: kuka, mikä, the place trio missä/mistä/mihin, milloin and miksi — and kuka and mikä decline.
- 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).
- Pronoun Declension TablesB1 — One-page reference: full case tables for personal pronouns, demonstratives (tämä/tuo/se), interrogatives (kuka/mikä) and the relative joka.