German Verbs - Wissen - to Know a Fact

Tenses and Sample Sentences

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Wissen is an irregular German verb that means to know a fact. German, like many other languages, has two different verbs that can correspond to the single English verb "to know." Like Spanish, Italian and French, for example, German makes a distinction between knowing or being familiar with a person or thing (kennen) and knowing a fact (wissen).

Wissen is often used with interrogatives: wann, wie, wo, warum, usw. For example, "Ich weiß, wo er ist." I know where he is.


How to Conjugate the Irregular German Verb Wissen

In the following chart you will find the conjugation of the irregular German verb wissen (to know). Although it is not a modal verb, the conjugation of wissen follows the same pattern as the modal verbs. Like the modals, and unlike normal German verbs, wissen has the same form for ich (first person sing.) and er, sie, es (third person singular).

The verb wissen is a stem-changing verb. That is to say, the infinitive's stem vowel i changes to ei in all the singular present tense forms (weiß), and to u in the past participle (gewusst). In many ways, as we said above, it behaves like a modal verb. Except for ihr wisst (formerly wißt), spelling reform has not affected wissen, so you should note that its singular forms are still spelled with an ess-zett (ß, except in Swiss German), while the plural forms use a double-s (ss).

This verb chart uses the new German spelling (die neue Rechtschreibung).

Irregular Verbs - Wissen

(Present Perfect)
Wissen - to know (a fact) Singular
ich weiß
I know
ich wusste
I knew
ich habe gewusst
I knew, have known
du weißt
you know
du wusstest
you knew
du hast gewusst
you knew, have known
er/sie weiß
he/she knows
er/sie wusste
he/she knew
er/sie hat gewusst
he/she knew, has known
Wissen - to know (a fact) Plural
wir/Sie/sie wissen
we/you/they have to
wir/Sie/sie wussten
we/you/they knew
wir/Sie/sie haben gewusst
we/you/they knew, have known
ihr wisst
you (pl.) know
ihr wusstet
you (pl.) knew
ihr habt gewusst
you (pl.) knew, have known



(Past Perfect)
Wissen - to know (a fact) Singular
ich hatte gewusst
I had known
ich werde wissen
I will know
du hattest gewusst
you had know
du wirst wissen
you knew
er/sie hatte gewusst
he/she had known
er/sie wird wissen
he/she will know
Wissen - to know (a fact) Plural
wir/Sie/sie hatten gewusst
we/you/they had known
wir/Sie/sie werden wissen
we/you/they will know
ihr hattet gewusst
you (pl.) had known
ihr werdet wissen
you (pl.) will know
ich/er würde wissen
I/he would know
ich/er wüsste
I/he would know
wir/sie würden wissen
we/they would know
wir/sie wüssten
we/they would know

Sample Sentences and Idioms with Wissen 

Er weiß Bescheid.
He knows all about it. (He's been kept informed.)

Weißt du, wann der Bus kommt?
Do you know when the bus is coming?

Ich habe nicht Bescheid gewusst.
I didn't know a thing about it.

Wer weiß?
Who knows? 

Wissen Sie, wie spät es ist?
Do you know (have) the time? 

Ich weiß (es) nicht.
I don't know.

Weißt du, wann der Zug abfährt?
Do you know when the train is departing? 

Sie weiß immer alles besser.
She always knows better.

Nicht, dass ich wüsste.
Not as far as I know. 

Man kann nie wissen.
You (just) never know.

Er will nichts von ihr wissen.
He wants nothing to do with her.


Was ich nicht weiß, macht mich nicht heiß.
What I don't know won't hurt me.