The first time someone asked me a question in fast French, my brain just… blue-screened. I was in a French class in Lyon, minding my own yak business, when the teacher suddenly turned to me and said something that sounded like:
“Alors, blablabla… qu’est-ce que tu en penses ?”
I understood exactly zero words. Instead of owning it, I panicked and said pardon /paʁ.dɔ̃/ — sorry — then smiled like that would magically answer her opinion question.
A classmate leaned over and whispered the two magic spells that would have saved me:
Je ne sais pas /ʒə nə sɛ pa/ — I don’t know.
Je ne comprends pas /ʒə nə kɔ̃.pʁɑ̃ pa/ — I don’t understand.
By the end of this guide, you’ll know when to use je ne sais pas vs je ne comprends pas, how to sound polite (or casual) in real conversations, and what people are mumbling when you hear something like “chais pas” instead of the neat textbook version.
Panic 101: Je Ne Sais Pas vs Je Ne Comprends Pas
Let’s get the core difference crystal-clear.
On first mentions:
- je ne sais pas /ʒə nə sɛ pa/ — I don’t know
- je ne comprends pas /ʒə nə kɔ̃.pʁɑ̃ pa/ — I don’t understand
They look similar because they share the same negative frame:
- ne … pas /nə … pa/ — not
The verbs in the middle are different:
- savoir /sa.vwaʁ/ — to know (a fact, information)
- comprendre /kɔ̃.pʁɑ̃dʁ/ — to understand (meaning, explanation, situation)
So:
- Use je ne sais pas when you don’t have the information.
- “What’s the capital of Mongolia?” → you genuinely don’t know.
- “What’s the capital of Mongolia?” → you genuinely don’t know.
- Use je ne comprends pas when the information is there, but your brain is not unpacking it.
- Someone explains grammar or directions and your brain goes “nope.”
- Someone explains grammar or directions and your brain goes “nope.”
Quick contrast:
| French | IPA | English |
| Je ne sais pas. | ʒə nə sɛ pa | I don’t know. (I don’t have the information.) |
| Je ne comprends pas. | ʒə nə kɔ̃.pʁɑ̃ pa | I don’t understand. (I can’t make sense of it.) |
Once you feel that difference, choosing between them gets a lot easier.
“Je Ne Sais Pas”: Owning “I Don’t Know” In French
Core Uses Of Je Ne Sais Pas
Use je ne sais pas /ʒə nə sɛ pa/ when:
- You don’t know the answer to a question
- You’re not sure about a fact
- You want to admit you don’t know, politely
Examples:
| French | IPA | English |
| Je ne sais pas. | ʒə nə sɛ pa | I don’t know. |
| Je ne sais pas encore. | ʒə nə sɛ pa ɑ̃.kɔʁ | I don’t know yet. |
| Je ne sais pas quoi dire. | ʒə nə sɛ pa kwa diʁ | I don’t know what to say. |
| Je ne sais pas où c’est. | ʒə nə sɛ pa u sɛ | I don’t know where it is. |
Softer And Stronger Alternatives
On first mentions:
- je ne suis pas sûr(e) /ʒə nə sɥi pa syʁ/ — I’m not sure
- je n’en sais rien /ʒə n‿ɑ̃ sɛ ʁjɛ̃/ — I don’t know at all / I have no idea
- je n’ai aucune idée /ʒə n‿e o.kyn i.de/ — I have no idea
| French | IPA | English |
| Je ne suis pas sûr(e). | ʒə nə sɥi pa syʁ | I’m not sure. |
| Je n’en sais rien. | ʒə n‿ɑ̃ sɛ ʁjɛ̃ | I don’t know at all. |
| Je n’ai aucune idée. | ʒə n‿e o.kyn i.de | I have no idea. |
Usage vibe:
- Je ne sais pas. → neutral, all-purpose.
- Je ne suis pas sûr(e). → softer, you might know but you’re not confident.
- Je n’en sais rien / je n’ai aucune idée. → stronger “no idea whatsoever,” often when you’re sure you don’t know.
Classroom & Everyday Examples
Tu connais la réponse ?
/ty kɔ.nɛ la ʁe.pɔ̃s/
Do you know the answer?
Je ne sais pas.
/ʒə nə sɛ pa/
I don’t know.
Tu vas faire quoi demain ?
/ty va fɛʁ kwa də.mɛ̃/
What are you going to do tomorrow?
Je ne sais pas encore.
/ʒə nə sɛ pa ɑ̃.kɔʁ/
I don’t know yet.
“Je Ne Comprends Pas”: Saying “I Don’t Understand” Without Drowning
Core Uses Of Je Ne Comprends Pas
Use je ne comprends pas /ʒə nə kɔ̃.pʁɑ̃ pa/ when:
- You don’t understand someone’s words
- You don’t understand an explanation or rule
- You’re lost in a conversation
| French | IPA | English |
| Je ne comprends pas. | ʒə nə kɔ̃.pʁɑ̃ pa | I don’t understand. |
| Je ne comprends pas bien. | ʒə nə kɔ̃.pʁɑ̃ pa bjɛ̃ | I don’t understand well. |
| Je ne comprends pas tout. | ʒə nə kɔ̃.pʁɑ̃ pa tu | I don’t understand everything. |
| Je ne comprends pas ce que vous dites. | ʒə nə kɔ̃.pʁɑ̃ pa sə kə vu dit | I don’t understand what you’re saying. |
Notice the nuance:
- Je ne comprends pas. → completely lost.
- Je ne comprends pas bien. → getting some of it, but not enough.
- Je ne comprends pas tout. → you understand partially, but not the whole thing.
Past Tense: “I Didn’t Understand”
On first mention:
- je n’ai pas compris /ʒə n‿e pa kɔ̃.pʁi/ — I didn’t understand
Use this when the moment has already passed, like when you didn’t understand instructions earlier.
| French | IPA | English |
| Je n’ai pas compris. | ʒə n‿e pa kɔ̃.pʁi | I didn’t understand. |
| Je n’ai pas bien compris. | ʒə n‿e pa bjɛ̃ kɔ̃.pʁi | I didn’t understand well. |
Example:
Tu as compris la question ?
/ty a kɔ̃.pʁi la kɛs.tjɔ̃/
Did you understand the question?
Non, je n’ai pas compris.
/nɔ̃ ʒə n‿e pa kɔ̃.pʁi/
No, I didn’t understand.
Polite Yak Mode: Softening “I Don’t Know/Understand”
French people really appreciate when you wrap your confusion in politeness instead of just throwing je ne comprends pas like a brick.
On first mentions:
- excusez-moi /ɛk.sky.ze mwa/ — excuse me (formal)
- pardon /paʁ.dɔ̃/ — sorry / excuse me
- s’il vous plaît /sil vu plɛ/ — please (formal)
Polite “I Don’t Understand”
| French | IPA | English |
| Excusez-moi, je ne comprends pas. | ɛk.sky.ze mwa ʒə nə kɔ̃.pʁɑ̃ pa | Excuse me, I don’t understand. |
| Pardon, je ne comprends pas bien. | paʁ.dɔ̃ ʒə nə kɔ̃.pʁɑ̃ pa bjɛ̃ | Sorry, I don’t understand well. |
| Excusez-moi, vous pouvez répéter, s’il vous plaît ? | ɛk.sky.ze mwa vu pu.ve ʁe.pe.te sil vu plɛ | Excuse me, can you repeat, please? |
| Plus lentement, s’il vous plaît. | ply lɑ̃.tə.mɑ̃ sil vu plɛ | More slowly, please. |
Polite “I Don’t Know”
| French | IPA | English |
| Je ne sais pas, désolé(e). | ʒə nə sɛ pa de.zɔ.le | I don’t know, sorry. |
| Je ne suis pas sûr(e), désolé(e). | ʒə nə sɥi pa syʁ de.zɔ.le | I’m not sure, sorry. |
| Honnêtement, je ne sais pas. | ɔ.nɛst.mɑ̃ ʒə nə sɛ pa | Honestly, I don’t know. |
When in doubt, add a softener:
- désolé(e) /de.zɔ.le/ — sorry
- honnêtement /ɔ.nɛst.mɑ̃/ — honestly
- je suis encore en train d’apprendre /ʒə sɥi ɑ̃ kɔʁ ɑ̃ tʁɛ̃ da.pʁɑ̃dʁ/ — I’m still learning
Example:
Je suis encore en train d’apprendre, je ne comprends pas tout.
/ʒə sɥi ɑ̃kɔʁ ɑ̃ tʁɛ̃ da.pʁɑ̃dʁ ʒə nə kɔ̃.pʁɑ̃ pa tu/
I’m still learning, I don’t understand everything.
Real-Life French: “Je Sais Pas”, “Je Comprends Pas” & Other Mumbles
Textbooks love je ne sais pas and je ne comprends pas. Real humans love shortcuts.
In spoken French, people often drop the “ne”:
- je sais pas /ʒə sɛ pa/ — I don’t know
- je comprends pas /ʒə kɔ̃.pʁɑ̃ pa/ — I don’t understand
- j’ai pas compris /ʒe pa kɔ̃.pʁi/ — I didn’t understand
You’ll also hear even more squished versions:
- chais pas /ʃɛ pa/ — super casual “I dunno”
- j’comprends pas /ʒkɔ̃.pʁɑ̃ pa/ — I don’t understand
As a learner:
- It’s totally fine (and safe) to say the full forms:
je ne sais pas, je ne comprends pas. - But you should recognize the short ones when you hear them.
Informal versions you’ll hear from younger speakers:
| French | IPA | English | Register |
| Je sais pas. | ʒə sɛ pa | I don’t know. | Informal, common |
| Chais pas. | ʃɛ pa | Dunno. | Very informal |
| Je comprends pas. | ʒə kɔ̃.pʁɑ̃ pa | I don’t understand. | Informal |
| J’ai pas compris. | ʒe pa kɔ̃.pʁi | I didn’t understand. | Informal |
You don’t need to use chais pas yet, but it’s useful to know that when someone says “j’sais pas, moi”, they are not casting a spell; they’re just saying they don’t know.
Region Notes: France, Québec, And Politeness Levels
You’ll hear je ne sais pas and je ne comprends pas all over the francophone world, but a few notes:
- In France, dropping the ne in speech (→ je sais pas, je comprends pas) is very common in everyday conversations, especially among younger people. In more formal contexts (job interview, presentation), people are more likely to keep ne.
- In Québec and some other regions, you’ll still hear similar patterns: je sais pas, je comprends pas, sometimes with different accents and slang.
- For writing (emails, texts to teachers, exams), stick to the full forms:
je ne sais pas, je ne comprends pas, je n’ai pas compris.
As a learner aiming for France French:
Speak politely with je ne sais pas / je ne comprends pas, train your ear to recognize je sais pas / je comprends pas, and you’ll be in a solid place.
Mini Dialogues: Confused But Polite In Real Situations
Each line: French, IPA, then natural English.
1. In French Class
Excusez-moi, je ne comprends pas cet exercice.
/ɛk.sky.ze mwa ʒə nə kɔ̃.pʁɑ̃ pa sɛ.t‿ɛɡ.zɛʁ.sis/
Excuse me, I don’t understand this exercise.
D’accord, je peux expliquer encore une fois.
/da.kɔʁ ʒə pø ɛk.spli.ke ɑ̃.kɔʁ yn fwa/
Okay, I can explain one more time.
Merci, je ne sais pas quoi faire ici.
/mɛʁ.si ʒə nə sɛ pa kwa fɛʁ i.si/
Thanks, I don’t know what to do here.
Pas de problème, on va le faire ensemble.
/pa də pʁɔ.blɛm ɔ̃ va lə fɛʁ ɑ̃.sɑ̃bl/
No problem, we’re going to do it together.
2. At A Train Station
Pardon, je ne sais pas où est le quai numéro trois.
/paʁ.dɔ̃ ʒə nə sɛ pa u ɛ lə kɛ ny.me.ʁo tʁwa/
Excuse me, I don’t know where platform three is.
C’est là-bas, tout droit, puis à gauche.
/sɛ la.ba tu dʁwa pɥi a ɡoʃ/
It’s over there, straight ahead, then to the left.
Merci beaucoup, je ne comprends pas encore bien le plan.
/mɛʁ.si bo.ku ʒə nə kɔ̃.pʁɑ̃ pa ɑ̃.kɔʁ bjɛ̃ lə plɑ̃/
Thank you very much, I still don’t understand the map very well.
Pas de souci, c’est normal.
/pa də su.si sɛ nɔʁ.mal/
No worries, that’s normal.
3. With A Friend Explaining A Movie
Alors, tu as compris la fin du film ?
/a.lɔʁ ty a kɔ̃.pʁi la fɛ̃ dy film/
So, did you understand the end of the film?
Franchement, je n’ai pas compris.
/fʁɑ̃ʃ.mɑ̃ ʒə n‿e pa kɔ̃.pʁi/
Honestly, I didn’t understand.
Moi non plus, je ne sais pas pourquoi il part.
/mwa nɔ̃ ply ʒə nə sɛ pa puʁ.kwa il paʁ/
Me neither, I don’t know why he leaves.
Bon, on regarde une explication sur Internet ?
/bɔ̃ ɔ̃ ʁə.ɡaʁd yn ɛk.spli.ka.sjɔ̃ syʁ ɛ̃.tɛʁ.nɛt/
Okay, shall we watch an explanation online?
Quick Reference: I Don’t Know / I Don’t Understand Cheat Sheet
| French | IPA | English |
| Je ne sais pas. | ʒə nə sɛ pa | I don’t know. |
| Je ne sais pas encore. | ʒə nə sɛ pa ɑ̃.kɔʁ | I don’t know yet. |
| Je ne sais pas quoi dire. | ʒə nə sɛ pa kwa diʁ | I don’t know what to say. |
| Je ne suis pas sûr(e). | ʒə nə sɥi pa syʁ | I’m not sure. |
| Je n’en sais rien. | ʒə n‿ɑ̃ sɛ ʁjɛ̃ | I don’t know at all. |
| Je n’ai aucune idée. | ʒə n‿e o.kyn i.de | I have no idea. |
| Je ne comprends pas. | ʒə nə kɔ̃.pʁɑ̃ pa | I don’t understand. |
| Je ne comprends pas bien. | ʒə nə kɔ̃.pʁɑ̃ pa bjɛ̃ | I don’t understand well. |
| Je ne comprends pas tout. | ʒə nə kɔ̃.pʁɑ̃ pa tu | I don’t understand everything. |
| Je ne comprends pas ce que vous dites. | ʒə nə kɔ̃.pʁɑ̃ pa sə kə vu dit | I don’t understand what you’re saying. |
| Je n’ai pas compris. | ʒə n‿e pa kɔ̃.pʁi | I didn’t understand. |
| Excusez-moi, je ne comprends pas. | ɛk.sky.ze mwa ʒə nə kɔ̃.pʁɑ̃ pa | Excuse me, I don’t understand. |
| Vous pouvez répéter, s’il vous plaît ? | vu pu.ve ʁe.pe.te sil vu plɛ | Can you repeat, please? |
| Plus lentement, s’il vous plaît. | ply lɑ̃.tə.mɑ̃ sil vu plɛ | More slowly, please. |
| Je parle encore un peu français. | ʒə paʁl ɑ̃.kɔʁ œ̃ pø fʁɑ̃.sɛ | I still speak only a little French. |
| Je suis encore en train d’apprendre. | ʒə sɥi ɑ̃kɔʁ ɑ̃ tʁɛ̃ da.pʁɑ̃dʁ | I’m still learning. |
| Je sais pas. | ʒə sɛ pa | I don’t know. (informal) |
| Je comprends pas. | ʒə kɔ̃.pʁɑ̃ pa | I don’t understand. (informal) |
| J’ai pas compris. | ʒe pa kɔ̃.pʁi | I didn’t understand. (informal) |
Five-Minute “Je Ne Sais Pas” Rescue Drill
- Core Pair Out Loud (1 minute)
Alternate slowly, three times each:
Je ne sais pas.
Je ne comprends pas.
Then add meaning out loud in English:
Je ne sais pas — I don’t know.
Je ne comprends pas — I don’t understand. - Soft Landing Practice (1 minute)
Say each polite version twice:
Excusez-moi, je ne comprends pas.
Pardon, je ne comprends pas bien.
Je ne sais pas, désolé(e). - Partial Understanding Lines (1 minute)
Practice NOT overusing “I don’t understand at all”:
Je ne comprends pas bien.
Je ne comprends pas tout.
Je n’ai pas bien compris. - Informal Ear Training (1 minute)
Say both the careful and casual versions:
Je ne sais pas. → Je sais pas.
Je ne comprends pas. → Je comprends pas.
Just to train your ear, even if you stick to the full forms when you speak. - Mini Real-Life Script (1 minute)
Say this mini-scene out loud three times:
Excusez-moi, je ne comprends pas bien. Vous pouvez répéter, plus lentement, s’il vous plaît ?
Then reply to yourself:
Je suis encore en train d’apprendre, je ne comprends pas tout.
Next time you’re lost in a French conversation, grab one of these lines instead of freezing. Confused but polite is the new fluent.
From Blank Stare To Brave Yak
Knowing how to say “I don’t know” and “I don’t understand” isn’t a sign of weakness in French — it’s a superpower. These phrases turn panic into progress: they keep the conversation going, invite help, and show you’re actually trying.
Once je ne sais pas and je ne comprends pas live comfortably in your mouth, you’re no longer the silent learner in the corner; you’re the yak who asks questions, admits confusion, and understands more with every “I don’t understand” you dare to say.