The IP Address Regex Python Validator helps you ensure that any string input follows the correct format for an IPv4 address. It’s perfect for use in server configurations, firewall filters, form validations, and networking tools. You can combine it with the Mac Address Regex Python Validator for device-level filtering, or pair it with the UUID Regex Python Validator when working with both identifiers and network data.
[A-Z]
: uppercase letters[a-z]
: lowercase letters[0-9]
: digits\.
: a literal dot+
: one or more of the preceding*
: zero or more of the preceding?
: optional (zero or one)^
: start of string$
: end of string
Test your APIs today!
Write in plain English — Qodex turns it into secure, ready-to-run tests.
Regular Expression - Documentation
What Is an IP Address?
An IP address is a unique identifier assigned to each device on a network. IPv4 addresses use four numbers (0–255) separated by dots, like:
To validate this format, we use a regex pattern that checks:
Exactly four octets
Each ranging from 0–255
Dot separators (.)
Regex Pattern for IP Address in Python
Here’s a regex that accurately validates standard IPv4 addresses:
Explanation:
25[0-5] → matches 250–255
2[0-4][0-9] → matches 200–249
1?[0-9]{1,2} → matches 0–199
The entire pattern ensures 4 such numbers, separated by .
Python Code Example
Use Cases
Form Validation: Validate user-entered IPs in web apps
Firewall Rules: Match and filter network IPs
Device Configuration: Validate inputs in local or cloud-based dashboards
Combine with: MAC Address Regex Python Validator or Date Regex Python Validator to sync IPs with timestamps
Pro Tips
🔄 Always trim whitespaces before validation (ip.strip())
🔒 Avoid trusting client-side validations—validate on the server too
🔀 Combine with subnet pattern checks for CIDR ranges
🧠 Use in scripts with the GUID Regex Python Validator to track devices over networks