Python regex ip

Question

I believe IP can only range from 0.0.0.0 to 255.255.255.255. I see lot's of complicated regex answers to match and validate IP addresses on stack overflow. Tell me what's wrong with mine.

ip = re.compile(r'[0-2]*[0-5]*[0-5]*\.[0-2]*[0-5]*[0-5]*\.[0-2]*[0-5]*[0-5]*\.[0-2]*[0-5]*[0-5]*\')

It works.

Try this regexp `'\b((25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)(\.|$)){4}\b'` — Ankit Jindal, Sep 14 '20 at 06:45

Robo Mop · Answer 1 · 2020-09-14T06:52:58.993

1

I absolutely understand why you used [0-2]*[0-5]*[0-5]*, and I believe I made a similar mistake once. The problem here is that it can only match 000-055, 100-155, 200-255. The code you need should be something like this:

(?:(?:[01]*[0-9][0-9])|(?:2[0-4][0-9])|(?:25[0-5]))

For each three digit sequence.

In essence, you're telling the regex that the input should have either:

any number from 0 to 199, given by [01][0-9][0-9]
or any number from 200 to 249, given by 2[0-4][0-9]
or any number from 250 to 255, given by 25[0-5]

edited Sep 14 '20 at 06:52

answered Sep 14 '20 at 06:47

Robo Mop

3,485
1
10
23

ahh I see it now. Thank you! – anika Sep 14 '20 at 06:53
No problem, glad to help. If the solution solved your problem completely, it'd be great if you could mark this answer as correct for future reference :) – Robo Mop Sep 14 '20 at 06:55
I'm a newbie SO wont let me mark it correct. I'll come back to this :) – anika Sep 14 '20 at 07:01

Python regex ip

1 Answers1