How to Say “I don’t know” in an Interview

In an interview, we are on stage and being judged. In the span of thirty to sixty minutes, a stranger needs to determine if we are sufficiently qualified for a job. In a span of thirty to sixty minutes, we must convince that stranger that we are the most amazing person who ever existed, because other people, similarly “qualified” are vying for the same position.

One of the most intrinsic fears we all share when interview is that question to which we don’t know the answer. When it comes, it’s always a surprise, there is no way we can have prepared for it — because if we knew what we didn’t know, we would find it out. Invariably, some interview at some point will contain a question where you have no knowledge, experience, or insight. Then what? What do you do? How do you salvage the interview?

Your brain is racing, you may be experiencing anxiety or dread, you may start to sweat. Everyone seems to be staring at you, the room feels too small, your collar is too tight or too low, you’re shifting in your chair. Your head is clanging with a single thought it can’t move past: I don’t know!

Then: What does that mean??

Then: How do I say this without losing all my credibility?

No One Knows Everything

STEP ONE: Just say it. Proclaim this dark secret to the world!

Before you can “salvage” the interview, you need to accept and understand one, tiny, impossible, critical thing: It’s okay not to know. No person in the world, no matter how good at their job they may be, knows everything. The scope of our world, the amount of knowledge to be learned, is impossibly large at this point. It’s no longer the Renaissance, where a person can study a few books and dabble in various experiments and profess to have all learning. Even in a single subject, our educational programs specialize because it is now impossible to learn everything about any one thing.

There are many reasons we might not know something. Perhaps we learned it in school but haven’t used it since and the memory is collecting dust somewhere in our brains; well, that’s okay — if you knew it once, you know that you can pick it up again. Perhaps we learned it on the job a few years ago but have forgotten — well, that’s because we’re not using it every day; once we start using it again, the dust will knock off and it will be a familiar pattern once more. Perhaps we never knew it — this is the most okay reason of all, but often the one we give ourselves the most torment over; just because we don’t know now doesn’t mean we can never know, doesn’t mean we’re stupid or incompetent. Not knowing just means we can’t access that information right now. It’s not a permanent state of being.

So, it’s okay to not know something. Give yourself that permission, that latitude; take a deep breath, smile, and tell your interviewer you don’t know.

You can say the exact phrase, “I don’t know,” or use something more tailored to the situation like, “I do not have experience with that procedure exactly,” or, “That sounds familiar but I can’t quite place it.”

Why You Don’t Know

STEP TWO: Follow the “I don’t know” with some words. Words that give context to your interviewer about your ignorance. Remember, your interviewer doesn’t know you, not yet. He doesn’t know how smart or resourceful you are. He doesn’t know if you’re tenacious or laid-back, honest or maneuvering, bright or stolid. Just leaving the question with, “I don’t know,” only tells him that you’ve given up. Show him your follow through, give him a window into your life and experience by explaining, briefly, the situation.

That’s a great question. I don’t know the answer. I haven’t worked with that technology before.

You know, I know I knew that 5 years ago when I was working on it, but I can’t quite remember right now.

Oh, wow, I don’t know! I studied that in school, and I remember doing well in the course and enjoying it, but it’s been a while and I don’t recall any specifics right now.

This explanation should be a sentence or less, or you can look like you’re making excuses or being deceptive.

Throw More Words at It

After this first exchange is where most interviewers and interview candidates lose the thread. If you want to keep your interviewer in the conversation with you, keep talking. Maybe you don’t know the answer to this question, but you know the answer to a similar question. Or maybe you can’t quite remember, but you can talk about what you do remember.

One of the questions that always trips me up when I start interviewing again, in my field, is: “What are the four tenants of Object-Oriented Programming?” When I was interviewing straight out of school, I knew these. Now, I use them; I don’t have to memorize the list because I implement it every day. So I say that:

Gosh, if you’d asked me that straight out of school, I would have been able to tell you. Now, I use OOP every day, so I don’t really think about it as a checklist, I just do it, if you know what I mean. Let me tell you what I do know, and if I miss any, I’m happy to talk about them if you remind me at the end…

Usually I’ll hit three of the four and then the interviewer will say, “What about encapsulation?” (This is the one I invariably forget about) Then I’ll say, “Oh, yes, that’s the one I always forget, thank you!” and I’ll explain what encapsulation is and give some examples.

By offering up the knowledge I do have I have done three things:

1. Shown the interviewer that I am attempting to answer the question in good faith, that I am not attempting to deceive him.
2. Demonstrated my honesty and forthrightness, my willingness to rise to a challenge.
3. Demonstrated that, like all humans, I am fallible.

Here are some other examples:

That’s a great question. I don’t know the answer. I haven’t worked with that technology before. I have worked with Y before, though, which is similar. Let me tell you a little about my work in Y and you let me know when I say something that sounds like what you’re looking for, so I can go into more detail.

You know, I know I knew that 5 years ago when I was working on it, but I can’t quite remember right now. If you’re comfortable talking about it in a little more detail, that may shake some things loose for me so I can speak about this intelligently.

Oh, wow, I don’t know! I studied that in school, and I remember doing well in the course and enjoying it, but it’s been a while and I don’t recall any specifics right now. I made an A in the class, so I know I can pick it up again. What I found fascinating about the subject was…

Ignorance is Impermanent

Just because you don’t know now, doesn’t mean you will never know. In your answer, fit in your willingness to learn, your confidence that you will remember once you start using it again, your ability to pick things up quickly, or your general enthusiasm for new things. Tell the interviewer, because he doesn’t know you yet, that you not knowing this thing is a transient state, and not indicative of your value.

Follow Up

After you have shared my knowledge and/or experience, if any, ask some follow-up questions. When answer a question where you don’t know the answer, it is very possible that you talked on tangential subject — these questions are your opportunity to realign with the interviewer and make sure you’re on the same page. This is especially important when answering a question with experience in a similar field/technology/situation.

If an interviewer asks me, “What do you know about telecommunications?” I say, “I’ve never worked in telecommunications, so nothing. I have, however, worked in the space industry.” Then I might start talking about the difficulties encountered in the space industry, like time problems, or government oversight. After a few sentences, I say, “Does any of that answer your question?” Sometimes they’ll say yes, sometimes no. If no, I ask for more details. “Like I said, I don’t know anything about telecommunications specifically, but I do want to answer your question. What makes telecommunications different from other engineering jobs, so I can try to speak to any tangential experience I may have?”

Don’t Lose the Interviewer

Sometimes, your interviewer starts to check out once you indicate that you don’t know an answer. Their minds are forming a snap judgement. The success of your interview can depend on you interrupting their thoughts in those moments.

When you’re in an in-person interview, watch your interviewers for non-verbal clues that can indicate when they’re checking out. Did they just frown and start to take notes? Did their eyes glaze over, or did they stop looking at you and start fiddling with a pen or staring at the door/clock/table? Do they seem suddenly fidgety or sleepy or irritated? Whatever reaction they have, if it’s not interest in you and what you’re saying, you need to get their attention back.

It’s harder to gauge this over a phone interview, but often people will make non-committal noises or unhappy noises into the phone — or there will be a long silence. A silence which you must fill with more words.

If you’re losing your interviewer’s attention, the best way to get it back is to get them to engage in the conversation. Ask them clarifying questions. Say things like, “know what I mean?” Laugh at yourself (kindly). Make a comment that is universal that they can agree with (like, “Gosh, I can’t believe I forgot that! Isn’t it strange how brains work sometimes?”).

Some people will resist this — they’ll think you’re trying to manipulate them, or “cheat” and get an answer out of them. If I ever get the feeling my interviewer is resisting being drawn back into the conversation, I try some bold, honest communication: “I don’t know what you’re thinking right now, but I know that I’ve said something that’s put you off. I want you to know that was not my intention and I’d like an opportunity to speak to whatever is bothering you.” Most of the time I get a response like, “Well, I can’t give you the answer, if you don’t know I not allowed to help you out.” So I’ll say, “I apologize if it seemed like I was fishing for an answer, that was, again, not my intention. I am very happy to talk about my experience and what I know, and I was only seeking a little more clarity around the question so I could answer it more fully. Here’s what I was thinking…. so when I asked X, I was trying to find out if I should talk about Y or Z.”

Failure

You won’t always be able to get them back. Some interviewers can’t take, “I don’t know,” for an answer. Some interviewers are suspicious and will see manipulation and deception in your attempts to humanize yourself and the interview process. That’s their problem, not yours.

I’ve had a few interviews, especially phone interviews, where I’ve left feeling like a complete dunce. My interview was unresponsive, or kept hammering me with questions after my first, “I don’t know,” response. If I don’t know anything about the telecommunications industry, I’m not going to know about the protocols it uses, or have experience in technologies specific to that industry. If an interviewer is asking me these things or causing me to feel stupid, it’s because either a) they’re a bully, or b) they can’t deviate from the script. In either case, I don’t want to work for that person.

If someone can’t accept that I am a human being, as fallible and imperfect as the next person, in an interview, that person is not worth my time. And frequently, the company that considers that person to be their best representative in an interview is also not worth my time. So, when I’m faced with a question I cannot answer, it’s my time to turn the tables around.

Telling them, “I don’t know,” is not just an opportunity for me to demonstrate my honesty, lateral thinking, and adaptability, but it is also a test. A test of my interviewer’s (and by association, their company’s) empathy for me, a lowly candidate. An opportunity for me to get a glimpse into what it might be like actually working in this company, a peek behind the curtain. The interview goes both ways.