Should You Use Certain or Specific? What’s the difference?

Certain means “sure, positive, not doubting,” and specific means “explicit or definite.” If that still doesn’t make sense, don’t worry. We’ll explore the differences between the two similar words.

What is “Certain”?

The adjective “certain” relates to the speaker and what they know. A “certain” item is an item that someone has in mind or has a quality of a particular object known to the speaker. For instance, you may have heard the phrase “a certain someone.”

The phrase implies that you know who someone is, but you aren’t willing to divulge the information yet. The “someone” has qualities that other people do not have.

In addition, you could be saying that you’re “certain” of who the someone was. I.e., you are positive without a doubt you know who the someone was.

The word originally came from Old French, meaning “fixed, resolved.”

What is “Specific”?

The noun “specific” is a unique attribute or quality that identifies an object from another object. For example, “That scar is a specific reminder of the gunfight.”

“Specific” relates to a singular idea that a “specific object” can only be that one object and nothing else, while a “certain object” can be anything within a range of objects the speaker believes it to be.

The word originates in late Latin and Old French, meaning “a kind, a sort, a special quality.”

Examples of Certain Vs. Specific

“This guy has certain skills.”

The speaker of this sentence has only seen personal evidence of the guy’s skills. He might not know what they are or what he can do. He is certain that the guy has skills, but he’s not 100% sure what they are.

“This guy has specific skills.”

Here, the speaker only refers to the skills he knows. He knows, without a doubt, that the guy has distinguishing skills. So much so that he can specify which skills he has.

“It’s a certain type of music”

Here, the sentence sounds more like an opinion that the speaker is sure of. The music sounds in such a way that maybe it mixes genres or changes keys. The speaker only knows that the music is different than other music but can’t explicitly explain why.

“It’s a specific type of music”

Here, the speaker knows the exact type of music. Instead of sounding kind of like jazz or sort of like rock, the music is definitely blues. Or it’s definitely heavy metal. That’s the specificity of a specific type. Only one type.


Certain and specific have synonyms just like any other words. Hopefully, they can shed some light on why they’re different.

Synonyms for Certain

  • Unquestionable
  • Sure
  • Indisputable
  • Particular
  • Explicit

Synonyms for Specific

  • Specified
  • Fixed
  • Distinct
  • Precise
  • Definite


It can be difficult to know when to use certain and when to use specific. Nowadays, we use “certain” when we base experiences 100% on our knowledge and not someone else’s. We use “specific” when we base experiences on both our knowledge and outside expertise. Both mean a singular thing or distinct object.