have sb's number SLANG
to know a lot about someone and so have an advantage over them:
Don't worry, I've got his number, he doesn't fool me.

[TahlilGaran] Advanced Learner's Dictionary ▲

have number
have (got) (someone's) number
to understand the way someone behaves.
They've got our number – they play harder against us than anybody else.

She seems to know exactly what people our age want – she definitely has our number.

have (someone's) number
[informal]
to know that someone is trying to do something bad and therefore be able to deal with them.
I'm not worried about Taylor. I've got his number and I know what to expect.

have (someone's) number
[informal]
to know that someone is trying to do something bad and therefore be able to deal with them.
I'm not worried about Taylor. I've got his number and I know what to expect.

[TahlilGaran] English Idioms Dictionary ▲

have number
to get the key information to be able to understand someone
"I have that man's number. He is a liar and cannot be trusted."

[TahlilGaran] English Idioms Dictionary ▲

have one's number
See: GET ONE'S NUMBER.
{v. phr.}, {informal} To find out or know what kind of person somebody is.
The boys soon had the new student's number.

The girls got their new roommate's number the first week of school.

[TahlilGaran] English Idioms Dictionary ▲

have someone's number
have (got) (someone's) number
to understand the way someone behaves.
They've got our number – they play harder against us than anybody else.

She seems to know exactly what people our age want – she definitely has our number.

have (someone's) number
[informal]
to know that someone is trying to do something bad and therefore be able to deal with them.
I'm not worried about Taylor. I've got his number and I know what to expect.

have (someone's) number
[informal]
to know that someone is trying to do something bad and therefore be able to deal with them.
I'm not worried about Taylor. I've got his number and I know what to expect.

[TahlilGaran] English Idioms Dictionary ▲

have someone's number
to get the key information to be able to understand someone
"I have that man's number. He is a liar and cannot be trusted."

[TahlilGaran] English Idioms Dictionary ▲