wiedzieć vs znać vs umieć: Which 'Know'?

English uses know for three completely different ideas: knowing a fact ("I know that it's Tuesday"), knowing a person or thing ("I know Anna," "I know Kraków"), and knowing how to do something ("I know how to swim"). Polish keeps these three apart with three different verbs — wiedzieć, znać, and umieć — and the good news is that the choice is almost mechanical: it is decided by what kind of thing follows the verb. Learn to read the complement and the verb picks itself.

The decision rule: look at the complement

A FACT — expressed with a że-clause or a wh-clause → wiedzieć A PERSON / PLACE / THING — a noun object (accusative) → znać A SKILL — expressed with an infinitiveumieć

That is the entire system. Each verb takes a different grammatical complement, so you rarely have to think about meaning at all — you think about form.

VerbMeansGovernment (what follows)Example
wiedziećknow a fact / information
  • że-clause or wh-clause (gdzie, kto, co…)
Wiem, że masz rację.
znaćbe acquainted with
  • accusative noun object
Znam Annę. / Znam Kraków.
umiećknow how to / have a skill
  • infinitive
Umiem pływać.
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Don't translate "know" and then hunt for a verb. Instead read what comes after "know" in your English sentence: a "that…" clause → wiedzieć; a name or noun → znać; a "how to…" → umieć. The complement is the trigger.

wiedzieć — knowing facts (+ a clause)

Wiedzieć is for information you hold in your head. It is almost always followed by a clause: że ("that") for statements, or a question word (gdzie, kto, co, kiedy, dlaczego, jak) for indirect questions.

Wiem, że pociąg ma opóźnienie.

I know that the train is delayed.

Nie wiem, gdzie ona mieszka.

I don't know where she lives.

Wiesz, kto to zrobił?

Do you know who did it?

Note the obligatory comma before że and before the question word — Polish punctuates every subordinate clause this way (see embedded questions).

Wiedzieć can take a bare object only in a few frozen, pronoun-like cases: Wiem to ("I know that"), Nic nie wiem ("I don't know anything"), Wiesz co? ("You know what?"). These work because to / co / nic stand in for a whole proposition — they are still "facts," just compressed.

Wiem to od dawna.

I've known that for a long time.

znać — being acquainted (+ accusative)

Znać means you are familiar with someone or something through experience — a person, a city, a song, a book, a language. It takes a direct object in the accusative, never a clause.

Znasz Marka? Pracuje ze mną.

Do you know Marek? He works with me.

Znam Kraków jak własną kieszeń.

I know Kraków like the back of my hand.

Czy znasz tę piosenkę?

Do you know this song?

A useful diagnostic: if you could replace "know" with "be familiar with" or "be acquainted with," it is znać. You are acquainted with Marek, familiar with Kraków, familiar with the song.

umieć — knowing how (+ infinitive)

Umieć is the "skill" verb: it means you have learned how to do something and can do it. It is followed by an infinitive. (It is one of Polish's modal-type verbs — see moc/umieć/wolno.)

Umiem pływać, ale nie umiem nurkować.

I can swim, but I can't dive.

Moja córka już umie czytać.

My daughter can already read.

Nie umiem gotować, ale się uczę.

I can't cook, but I'm learning.

In speech, umieć often overlaps with móc ("can/be able") and potrafić ("manage to / be capable of"). The distinction: umieć = a learned skill ("know how"); móc = possibility/permission in the moment ("Can I sit here?"). For a trained ability, prefer umieć.

The sorting test

Run any "know" sentence through three questions:

  1. Does "know" introduce a "that…" / "where…" / "who…" clause?wiedzieć. ("I know that he's here.")
  2. Is the object a person, place, or named thing?znać. ("I know him," "I know Warsaw.")
  3. Is the object "how to + verb"?umieć. ("I know how to drive.")

The famous trio, side by side:

Znam go.

I know him (acquainted) — znać + accusative.

Wiem, że jest tutaj.

I know that he's here (a fact) — wiedzieć + clause.

Umiem prowadzić samochód.

I know how to drive a car (a skill) — umieć + infinitive.

Three Englishes all use "know"; three Polishes use three verbs, sorted purely by complement.

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A quick spoken-Polish shortcut: wiedzieć and znać share the first person "I know," but listen for the ending. "Wiem…" is always followed by a clause (wiem, że…); "znam…" is always followed by a noun (znam go). If you catch yourself about to put a noun after wiem, switch to znam.

The classic "answer" trap

The biggest pitfall hides in the word answer / odpowiedź, because in English "Do you know the answer?" feels factual. But odpowiedź is a noun object, not a clause — so it takes znać, not wiedzieć:

Znasz odpowiedź?

Do you know the answer? — odpowiedź is a noun → znać.

Wiesz, jaka jest odpowiedź?

Do you know what the answer is? — now it's a clause → wiedzieć.

The meaning is nearly identical; the grammar decides the verb. If you front a noun (odpowiedź, numer, adres, nazwisko) use znać; if you unpack it into a clause (jaka jest…, jaki jest…) use wiedzieć.

Znasz jego numer telefonu?

Do you know his phone number?

Nie wiem, jaki jest jego numer.

I don't know what his number is.

Common Mistakes

❌ Wiem odpowiedź.

Incorrect — a bare noun object can't follow wiedzieć.

✅ Znam odpowiedź.

I know the answer.

This is the single most common error. English "I know the answer" looks factual, so learners grab wiem — but odpowiedź is a noun object, which belongs to znać.

❌ Znam, że masz rację.

Incorrect — znać cannot take a że-clause.

✅ Wiem, że masz rację.

I know that you're right.

A że-clause is a fact, so it must be wiedzieć. Reserve znać for noun objects.

❌ Wiem pływać.

Incorrect — a skill (infinitive) doesn't follow wiedzieć.

✅ Umiem pływać.

I know how to swim.

A "how to + verb" skill is always umieć + infinitive. English "know how to" maps to umieć, never wiedzieć.

❌ Czy wiesz Annę?

Incorrect — a person is a noun object, not a fact.

✅ Czy znasz Annę?

Do you know Anna?

People are the textbook case of znać + accusative. Wiedzieć a person is impossible — you can only know facts about her: Wiem, kim jest Anna.

❌ Umiem, że to prawda.

Incorrect — umieć takes a skill, not a fact-clause.

✅ Wiem, że to prawda.

I know that it's true.

Key Takeaways

  • The choice is decided by the complement, not the meaning: clause → wiedzieć, noun (accusative) → znać, infinitive → umieć.
  • wiedzieć + że/wh-clause = a fact. znać + accusative = a person/place/thing you're acquainted with. umieć + infinitive = a learned skill.
  • The "answer" trap: a noun (odpowiedź, numer, adres) takes znać; unpack it into a clause (jaka jest…) and it becomes wiedzieć.
  • People are always znać ("I know him" = znam go); you can only wiedzieć facts about them.
  • "Know how to" is always umieć
    • infinitive.

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Related Topics

  • wiedzieć — to know (a fact)A2Full reference for the irregular verb wiedzieć ('to know a fact'): present wiem/wiesz…/wiedzą, past wiedział/wiedziała/wiedzieli/wiedziały, imperative wiedz — and the three-way split wiedzieć vs znać vs umieć.
  • znać — to know (be acquainted)A2Full conjugation of znać / poznać ('be acquainted with' / 'get to know, meet'): present znam/znasz/zna…/znają, past znał, the meet-phrase Miło mi cię poznać, and the split znać vs wiedzieć vs umieć.
  • Ability and Permission: móc, umieć, potrafić, wolno, możnaA2Polish splits English 'can' into several words — móc (situational possibility/permission), umieć and potrafić (learned skill), and the impersonal można and wolno — and choosing the right one is the whole game.
  • Tricky Verb Pairs: prosić/pytać, grać w/na, znać/wiedziećB1English verbs that split into two or three Polish verbs depending on the complement — prosić vs pytać ('ask'), grać w vs na ('play'), znać/wiedzieć/umieć ('know'), uczyć vs uczyć się ('teach/learn').
  • mówić / powiedzieć — to say, speak, tellB1Full reference for the suppletive pair mówić (impf, 'speak/talk') / powiedzieć (pf, 'say/tell'): present mówię/mówisz…, future powiem/powiesz…/powiedzą (the wiedzieć-stem), imperatives mów / powiedz — and when to use each.
  • Indirect (Embedded) QuestionsB1How to fold a question inside a bigger sentence: yes/no embedded questions use czy 'whether', wh-embedded questions keep their question word, a comma always precedes the clause — and, unlike English, Polish never reshuffles the word order.