10 Ways to Say “I’m Not Sure”
In English conversations, it’s just as important to express uncertainty as it is to express confidence. When you need to communicate that you don’t have all the facts, don’t know the answer, or aren’t ready to commit, simply saying “I’m not sure” can feel a little plain. Learning 10 Ways to Say “I’m Not Sure” gives you the flexibility to express your doubt politely, professionally, or casually, making you sound much more natural and fluent.
Phrases for Expressing Uncertainty
These expressions are divided by the tone you want to convey: from being completely unsure to needing more information.
Polite and Professional Doubt
These phrases are ideal for formal settings, like work meetings, official emails, or conversations with people you don’t know well. They maintain a respectful tone while admitting uncertainty.
- I can’t say for certain.
- Meaning & Use: This is a professional and definite way of saying you don’t know or can’t promise the information is correct. It politely tells the listener that the information is unconfirmed.
- Example: “Will the stock price go up next week?” → “I can’t say for certain, but the trends look positive.”
- I don’t have that information right now.
- Meaning & Use: Use this when you are expected to know the answer but don’t have it immediately available. It implies you can find the information later. This is often followed by “I will check.”
- Example: “What was the total revenue for the third quarter?” → “I don’t have that information right now. I will check the report and email you.”
- That’s hard to say.
- Meaning & Use: This is used when the question itself is difficult, complex, or depends on many unknown factors. It explains why you can’t give a simple “yes” or “no” answer.
- Example: “Do you think the new product will be successful globally?” → “That’s hard to say. It depends heavily on local market acceptance.”
- I haven’t made up my mind yet.
- Meaning & Use: Use this when you are hesitating about a decision or choice. It indicates that you are still thinking and need more time before committing.
- Example: “Have you decided if you’ll take the job offer?” → “I haven’t made up my mind yet. I need one more day to consider it.”
Casual and Common Expressions
These phrases are relaxed and perfect for everyday chats with friends or family. They are very common among native speakers.
- I have no idea.
- Meaning & Use: A strong, direct, and slightly emphatic way to say you definitely don’t know the answer. Use this only in casual settings, as it can sound too abrupt in a professional context.
- Example: “Where did David go after the party?” → “I have no idea. He just disappeared.”
- I’m drawing a blank.
- Meaning & Use: This means you are trying to remember or think of the answer, but your mind is empty. It’s an idiomatic way to say your memory is failing you right now.
- Example: “What was the name of that restaurant we went to last summer?” → “I’m drawing a blank. Was it Italian?”
- Your guess is as good as mine.
- Meaning & Use: A very common, casual phrase meaning that you and the other person have the exact same amount of knowledge (or lack thereof). You are both equally unsure.
- Example: “Why did the bus stop suddenly?” → “Your guess is as good as mine. Maybe there’s traffic ahead.”
- I’m on the fence.
- Meaning & Use: This means you are undecided between two different options. The image is of someone sitting on a fence, unable to jump to one side or the other.
- Example: “Are you going to move to New York or stay in London?” → “I’m on the fence. Both places have great job opportunities.”
Softening the Uncertainty
These phrases politely soften your lack of knowledge and often invite the other person to share their opinion.
- I couldn’t tell you.
- Meaning & Use: A polite way of saying “I don’t know.” It sounds softer than “I don’t know” because the focus is on the inability to answer, not just the lack of knowledge.
- Example: “How long will the construction project take?” → “I couldn’t tell you. The weather is going to slow them down.”
- I’m not 100% sure.
- Meaning & Use: This implies that you have an idea or a guess, but you are not completely confident in it. It shows a slight degree of certainty while still expressing doubt.
- Example: “Did the store close at 9 PM tonight?” → “I’m not 100% sure, but I think they extended their hours until 10.”
Phrases in Conversation
Here are a few realistic dialogues showing how to use these 10 Ways to Say “I’m Not Sure” in context.
Dialogue 1 (Casual/Memory)
Sarah: “Do you remember the main character’s name in that book we read?”
Mark: “I’m drawing a blank. Let me check my bookshelf later.”
Dialogue 2 (Professional/Decision)
Team Leader: “Do you think we should launch the product next month or wait for the holiday season?”
Colleague: “That’s hard to say. If we wait, we risk competitors getting ahead. I haven’t made up my mind yet.”
Dialogue 3 (Common Doubt)
Tourist: “Excuse me, does this train stop at the Central Station?”
Local: “I’m not 100% sure. You might want to ask the conductor.”
Quick Tips: When to Use
| Situation | Recommended Expression | Why? |
| The answer is complex or unknown | That’s hard to say. / I can’t say for certain. | These are professional and respectful of the complexity of the question. |
| You are struggling to remember a fact | I’m drawing a blank. / I have no idea. | These clearly signal a lack of memory. |
| You need more time to make a choice | I haven’t made up my mind yet. / I’m on the fence. | These communicate that you are actively considering your options. |
| You need to find the information first | I don’t have that information right now. / I couldn’t tell you. | These are polite ways to promise to find the answer later. |
Having a variety of phrases like these 10 Ways to Say “I’m Not Sure” makes you a much more effective communicator in English. It shows that you can express nuance and honesty, which is key to sounding fluent.
Don’t be afraid to admit you don’t know something! Try using “That’s hard to say” today in a conversation. You’ll see how natural it feels!