What Does “Cap” Mean in English Slang?

If you hang out on TikTok, Twitter, YouTube, or chat with younger English speakers, you’ve probably heard someone say:

“That’s cap.”
“No cap.”

At first, it sounds confusing. What does a cap (like a hat?) have to do with conversations?

Don’t worry — this slang word isn’t about fashion. It has a totally different meaning in modern, casual English.

Let’s break it down.

What “Cap” Means

In slang, “cap” means a lie or something untrue.

• “That’s cap” = That’s not true / That’s a lie
  
  

• “No cap” = I’m being honest / This is the truth
  
  

So it’s basically a quick way to call something true or false — especially in casual conversations or on social media.

Let’s see some real examples.

Examples of “Cap” and “No Cap”

• Friend 1: “I can run a mile in 4 minutes.”
  Friend 2: “That’s cap.”
  ( = I don’t believe you. That’s a lie.)
  
  

• Classmate: “You’re the best player on the team, no cap.”
  ( = I’m telling the truth. You really are.)
  
  

• TikTok comment: “This is the funniest video I’ve ever seen, no cap.”
  ( = Honestly, this video is really funny.)
  
  

• Texting a friend:
  “He said he’s rich but lives with his mom. Cap.”
  
  

As you can see, the word “cap” works like a stamp of truth or lie. It is fast, simple, and expressive.

Where Did “Cap” Come From?

The slang word “cap” comes from African American Vernacular English (AAVE). Originally, “capping” meant bragging or lying about something.

Over time, younger people shortened it to just “cap” and turned it into a reply word just like how “bet” evolved.

Now, it’s all over social media and used in everyday speech, especially among Gen Z.

Is “Cap” Formal or Informal?

“Cap” is definitely informal and very slangy.
You should only use it in relaxed, casual settings.

✅ Okay to use:

• On social media
  
  

• In group chats
  
  

• With friends
  
  

• In memes or jokes
  
  

❌ Do not use:

• In school essays
  
  

• In business meetings
  
  

• In interviews
  
  

• In formal writing
  
  

If you want to sound more neutral or formal, say:

• “That’s not true.”
  
  

• “I don’t believe you.”
  
  

• “Honestly…” instead of “no cap”
  
  

Quick Review: How to Use “Cap”

Expression

Meaning

Example

That’s cap

That’s a lie

“She said she’s never late.” → “Cap.”

No cap

I’m being honest

“You’re so good at drawing, no cap.”

Cap

Not true / Lying

“He said he’s famous.” → “Cap.”

Final Thoughts

The slang word “cap” is short, sharp, and everywhere in modern English. If someone says “cap,” they mean “I don’t believe that.” If they say “no cap,” they’re being totally honest.

You don’t have to use it but now you can understand it when you hear it online, in music, or in casual chats.

👉 In the next blog post, we’ll look at another one-word slang expression that’s just as popular and just as easy to misuse:
“Flex.”