Odd vs That’s weird

When to use each in English, with meaning, register, and examples.

Odd

Top 1,000 (very common)B1adjective

That’s weird

InformalTop 2,000 (common)
Most formal: OddMost common: Odd
 OddThat’s weird
Pronunciation🇬🇧 /["/ɒd/"]/🇺🇸 /["/ɑːd/"]/🇬🇧 //ðæts wɪəd//🇺🇸 //ðæts wɪrd//
MeaningStrange or unusual.That is strange or unusual.
ExampleIt's odd how he always knows what I'm thinking.The lights flickered, and I thought, 'That’s weird.'
RegisterNeutralInformal
How commonTop 1,000 (very common)Top 2,000 (common)
CEFR levelB1-
Part of speechadjective
Collocationsbe, feel, look, extremely, fairly, very, how odd, it is odd to think, something oddThat's weird timing, That's weird behavior, That's weird to say, That's weird, isn't it?, That’s weird for sure
Antonymseven, normal, common-
Common mistakesUsing 'odd' to describe something that is simply different but not strange., Confusing 'odd' with 'oddly', which is an adverb., 'Odd' used incorrectly in positive contexts when it should be neutral or negative.Using in overly formal contexts., Confusing with 'That's strange' - similar but 'weird' has a stronger connotation., Not using the contraction (That's) - sounds more natural to shorten.
Usage notesUse 'odd' to describe something that is not normal or makes you feel uneasy. It can refer to behavior, things, numbers, etc. Avoid using it in very formal situations.Use when something feels odd or unexpected; appropriate in casual contexts but can seem unprofessional in formal settings.

See it in real clips

That’s weird

Frequently asked questions: Odd vs That’s weird

What's the difference between Odd and That’s weird?

Odd: Strange or unusual. That’s weird: That is strange or unusual.

Which is more formal: Odd and That’s weird?

Odd is the most formal of these.

Which is more common: Odd and That’s weird?

Odd is the most common in everyday English.

Can you show an example of each?

Odd: It's odd how he always knows what I'm thinking. That’s weird: The lights flickered, and I thought, 'That’s weird.'

Can I use Odd and That’s weird interchangeably?

Not always. Odd and That’s weird are related and overlap in some contexts, but they differ in register, how common they are, and usage, so swapping one for another can change the meaning or tone. Check the differences above before substituting.

Related comparisons