French grammar · Beginner
Savoir in French: Knowing Facts and Knowing How
Savoir means to know a fact or to know how to do something, and conjugates je sais, tu sais, il sait, nous savons, vous savez, ils savent. It takes a clause, an infinitive, or nothing at all, but never a person: knowing people is connaître.
Je ne sais pas où il habite.
I don't know where he lives.
What it is
Savoir is knowledge you can state or perform. If you can put what you know into a clause, savoir is the verb: je sais qu'il est parti, je sais où elle habite, je sais pourquoi. If you can do it because you learned how, savoir is also the verb: je sais nager. What savoir cannot do is take a person or a place as its object.
Je sais qu'elle est médecin, mais je ne la connais pas. — I know she's a doctor, but I don't know her.
How to spot it
Look at what follows. A que clause, a question word, an infinitive, or nothing at all means savoir. A bare noun naming a person, a place, or a work of art means connaître.
- Je sais qu'il viendra. — I know he'll come. (clause)
- Tu sais quand ça commence ? — Do you know when it starts ? (question word)
- Elle sait conduire. — She can drive. (infinitive)
- Je ne sais pas. — I don't know. (nothing at all)
Savoir followed directly by a noun is possible only for things you have learned by heart: savoir sa leçon, savoir le chemin.
Savoir Quick Reference
Savoir at a glance
| Structure | Meaning | Example |
|---|---|---|
| savoir que + indicative | to know that | je sais qu'il ment — I know he's lying |
| savoir + question word | to know when, where, why | je sais où c'est — I know where it is |
| savoir + infinitive | to know how to | je sais nager — I can swim |
| savoir si | to know whether | je ne sais pas s'il vient — I don't know if he's coming |
| j'ai su | found out | j'ai su la nouvelle hier — I heard the news yesterday |
| je savais | already knew | je savais tout — I knew everything |
| sache / sachez | imperative | sachez que… — be aware that… |
| que je sache | as far as I know | il n'est pas venu, que je sache |
Common Savoir Examples in French
Savoir across its structures:
Knowing a Fact
- Je sais que tu as raison.
- I know you're right.
- Tu sais combien ça coûte ?
- Do you know how much it costs ?
- Personne ne sait pourquoi il est parti.
- Nobody knows why he left.
- Nous ne savions pas qu'elle était malade.
- We didn't know she was ill.
Savoir que takes the indicative, even when negated, because knowledge is not a matter of doubt.
Knowing How
- Il sait faire du vélo depuis l'âge de cinq ans.
- He's been able to ride a bike since he was five.
- Est-ce que vous savez utiliser ce logiciel ?
- Do you know how to use this software ?
- Elle sait écouter.
- She knows how to listen.
- Je ne sais pas dire non.
- I don't know how to say no.
French drops the how: savoir plus an infinitive already means know how to.
Finding Out
- J'ai su la vérité par un collègue.
- I found out the truth from a colleague.
- Quand as-tu su qu'elle partait ?
- When did you find out she was leaving ?
- On a su plus tard qu'il avait menti.
- We later learned he had lied.
- Tu sauras bientôt.
- You'll find out soon.
In the passé composé savoir marks the moment the information arrived, not the state of knowing.
Softening and Hedging
- Je ne sais pas trop.
- I'm not really sure.
- Tu sais, ce n'est pas si grave.
- You know, it's not that serious.
- Sachez que nous ferons notre possible.
- Please be aware that we'll do what we can.
- Il n'est pas encore rentré, que je sache.
- He isn't back yet, as far as I know.
Tu sais at the start of a sentence works exactly like English you know, as a conversational cushion.
How Savoir Behaves
The conjugation is short and the syntax is generous, but three points regularly cause trouble.
Sai- in the Singular, Sav- in the Plural
The present splits into two stems, but unlike pouvoir and vouloir, savoir keeps the plural stem for ils: ils savent, not saivent.
Je sais, nous savons, ils savent.
I know, we know, they know.
sais, sais, sait, savons, savez, savent.
No Preposition Before the Infinitive
Savoir takes a bare infinitive. English needs how to, but French folds that meaning into the verb itself, so adding comment produces a different sentence about knowing a method.
Elle sait négocier.
She knows how to negotiate.
savoir + infinitive = know how to.
Savoir Que Keeps the Indicative
Even in the negative and in questions, savoir que takes the indicative. It belongs to the group of verbs whose mood never varies, unlike penser and croire.
Je ne savais pas qu'il était marié.
I didn't know he was married.
savoir que → indicative, always.
The Tense Changes the Meaning
Knowledge is a state, so the imparfait is the neutral past. The passé composé marks the instant the knowledge arrived, which comes out in English as found out.
Je le savais déjà quand je l'ai su officiellement.
I already knew it when I was officially told.
savais = knew, ai su = found out.
Three Irregular Forms Come From the Same Stem
Sach- gives the subjunctive, the imperative, and the present participle: que je sache, sachez, sachant. Learning the stem once covers all three.
Ne sachant pas quoi faire, il a attendu.
Not knowing what to do, he waited.
sach- → sache, sachez, sachant.
Common Mistakes with Savoir
Incorrect: Je sais ton frère. — I know your brother.
Correct: Je connais ton frère. — I know your brother.
Savoir cannot take a person as its object. Familiarity with people, places and works always goes through connaître, whatever the English sentence looks like.
Incorrect: Je sais comment nager. — I know how to swim.
Correct: Je sais nager. — I know how to swim.
The how is already inside savoir. Adding comment turns the sentence into a claim about knowing the technique, which is not what the English means.
Incorrect: Je ne sais pas qu'il soit parti. — I don't know that he's left.
Correct: Je ne sais pas qu'il est parti. — I don't know that he's left.
Unlike penser and croire, savoir keeps the indicative even when negated. Its clause reports information rather than an opinion, so nothing licenses the subjunctive.
Incorrect: Je savais la nouvelle ce matin. — I heard the news this morning.
Correct: J'ai su la nouvelle ce matin. — I heard the news this morning.
Ce matin points at the moment the information arrived, which is the passé composé reading. The imparfait would mean you already had the news throughout the morning.
Savoir Conjugated
Four stems: sai- and sav- in the present, sav- for the imparfait, saur- for the future and conditional, and sach- for the subjunctive, imperative and participle.
The Simple Tenses
The future stem saur- is irregular but perfectly regular in its endings, so je saurai and tu sauras follow the usual pattern.
| Pronoun | présent | imparfait | futur simple | conditionnel |
|---|---|---|---|---|
| je / j' | sais | savais | saurai | saurais |
| tu | sais | savais | sauras | saurais |
| il / elle / on | sait | savait | saura | saurait |
| nous | savons | savions | saurons | saurions |
| vous | savez | saviez | saurez | sauriez |
| ils / elles | savent | savaient | sauront | sauraient |
Je ne saurais vous dire is a formal way of saying I couldn't tell you, using the conditional with no si clause.
Compound Tenses, Subjunctive and Imperative
Savoir takes avoir and its participle is su. The imperative is used to give information rather than orders.
| Pronoun | passé composé | plus-que-parfait | subjonctif (que…) | impératif |
|---|---|---|---|---|
| je / j' | ai su | avais su | sache | — |
| tu | as su | avais su | saches | sache |
| il / elle / on | a su | avait su | sache | — |
| nous | avons su | avions su | sachions | sachons |
| vous | avez su | aviez su | sachiez | sachez |
| ils / elles | ont su | avaient su | sachent | — |
Sachez que is the standard formula for be aware that in letters and announcements.
Savoir Against Connaître
Both translate as to know, and both are frequent, so it is worth seeing the two conjugations together. Connaître keeps a circumflex before a t.
| Pronoun | savoir | connaître |
|---|---|---|
| je / j' | sais | connais |
| tu | sais | connais |
| il / elle / on | sait | connaît |
| nous | savons | connaissons |
| vous | savez | connaissez |
| ils / elles | savent | connaissent |
Connaître always needs a direct object; savoir usually needs a clause. That syntactic difference is more reliable than any meaning-based rule.
Sachez, Que Je Sache, and Savoir Versus Connaître
One irregular stem produces a set of very useful fixed phrases, and one boundary is worth patrolling carefully.
The sach- forms
Sache, sachons and sachez are the imperative, and sachant is the present participle. They are used to inform rather than to command.
- Sachez que le magasin ferme à dix-neuf heures.
- Please note that the shop closes at seven.
- Sache que je pense à toi.
- Know that I'm thinking of you.
- Ne sachant rien, elle n'a rien dit.
- Knowing nothing, she said nothing.
- Il faut que tu saches la vérité.
- You need to know the truth.
Sachez que is the polite equivalent of English please be aware that in customer service and correspondence.
Que je sache and à savoir
Two frozen phrases. Que je sache means as far as I know and always follows the statement it qualifies; à savoir introduces a specification, like English namely.
- Elle n'a pas démissionné, que je sache.
- She hasn't resigned, as far as I know.
- Il manque deux documents, à savoir le contrat et la facture.
- Two documents are missing, namely the contract and the invoice.
- Il est reparti sans rien dire, que je sache.
- He left again without saying anything, as far as I know.
Que je sache uses the subjunctive even though nothing in the sentence appears to trigger it.
Savoir versus connaître
Connaître means to be familiar with and always takes a direct object: a person, a place, a book, a subject. Savoir means to hold information and takes a clause or an infinitive.
- Je connais Paris, mais je ne sais pas où est ce musée.
- I know Paris, but I don't know where that museum is.
- Elle connaît bien la question.
- She knows the subject well.
- Tu connais cette chanson ? Tu sais qui l'a écrite ?
- Do you know this song ? Do you know who wrote it ?
- Je sais sa réponse par cœur.
- I know his answer by heart.
The last example is the narrow case where savoir takes a noun: something learned and reproducible.
Savoir FAQs
- How do you conjugate savoir in the present tense?
- Je sais, tu sais, il sait, nous savons, vous savez, ils savent. The past participle is su, the future stem is saur-, and the subjunctive and imperative both use sach-, giving que je sache and sachez.
- What is the difference between savoir and connaître?
- Savoir is for information and skills and takes a clause or an infinitive; connaître is for familiarity and always takes a direct object. Je sais où elle habite but je connais son quartier.
- How do you say I can swim in French?
- Je sais nager. Swimming is a learned skill, so it belongs to savoir. Je peux nager would mean nothing is stopping you today, which is a different statement about circumstances.
- Does savoir que take the subjunctive?
- No, never, even when it is negated or in a question. Je ne sais pas qu'il est là and sais-tu qu'il est là both keep the indicative, which distinguishes savoir from penser and croire.
- What does que je sache mean?
- As far as I know. It is a fixed phrase, always in the subjunctive, and it comes after the statement it hedges: il n'a pas appelé, que je sache. There is no way to rearrange it.