Use our free IP Address Validator to check whether an IPv4 or IPv6 address is correctly formatted. Enter an address to identify its IP version, view its normalized format, and understand whether it belongs to a private, shared, loopback, link-local, or other special-purpose range.
The validator works directly in your browser. No installation, account, or third-party IP lookup service is required.
Check an IPv4 or IPv6 address
Enter an IP address to check its format and learn whether it falls within a common private, shared, or special-use range.
- Normalized address
- Address range
The entered IP is checked in your browser; this validator does not submit it to a server. It does not find your own IP, verify connectivity, identify an ISP, or determine physical location. Other site services may still process normal page visits.
How to Use the IP Address Validator
Checking an IP address takes three simple steps:
- Enter an IP address. Type or paste an IPv4 address such as
192.168.1.1or an IPv6 address such as2001:db8::1. - Select Validate IP. The tool checks the address format and identifies its version.
- Review the result. See whether the address is valid, its normalized representation, and the applicable address-range classification.
You can use the example buttons to try different address types or select Clear to start again.
Enter only the IP address. The tool does not accept domain names, complete URLs, port numbers, subnet prefixes such as /24, or IPv6 zone identifiers.
What Does the IP Address Validator Check?
The validator examines the structure of an IP address and compares it against several common special-purpose address ranges.
IPv4 Address Validation
An IPv4 address contains four decimal numbers separated by periods. Each number must be between 0 and 255.
For example, 192.168.1.1 is a valid IPv4 address, while 192.168.1.256 is invalid because 256 exceeds the permitted range.
The validator also rejects ambiguous IPv4 formatting, including octets containing leading zeros such as 192.168.001.1.
IPv6 Address Validation
IPv6 addresses use hexadecimal numbers separated by colons. Unlike IPv4, IPv6 supports compressed notation, where consecutive groups of zeros can be shortened using ::.
For example, 2001:0db8:0:0:0:0:0:1 is valid and can be written in its normalized form as 2001:db8::1.
The tool checks IPv6 formatting, including compressed addresses and supported IPv4-mapped representations.
IP Address Range Classification
A correctly formatted IP address can belong to different address categories.
| IP Address | Example Classification |
|---|---|
192.168.1.1 | Private IPv4 |
100.64.0.1 | Shared address space (CGNAT) |
127.0.0.1 | Loopback |
169.254.1.20 | Link-local IPv4 |
2001:db8::1 | Documentation IPv6 |
fe80::1 | Link-local IPv6 |
These classifications describe address ranges, not whether a device is connected to the internet or whether an address is currently assigned.
What Is the Difference Between IPv4 and IPv6?
IPv4 and IPv6 are two versions of the Internet Protocol used to identify network interfaces and support communication between devices.
| Feature | IPv4 | IPv6 |
|---|---|---|
| Address length | 32 bits | 128 bits |
| Format | Decimal numbers with periods | Hexadecimal groups with colons |
| Example | 192.168.1.1 | 2001:db8::1 |
| Address capacity | About 4.3 billion possible addresses | Approximately 3.4 × 10³⁸ possible addresses |
| Private or local addressing | RFC 1918 private ranges | Unique-local and link-local ranges |
IPv6 provides a much larger address space than IPv4. Both versions are used in modern networks, and some connections support both simultaneously.
Private IP Addresses, Public IP Addresses, and CGNAT
Understanding an address category can help when checking a home router, configuring a network, or troubleshooting an internet connection.
Private IP addresses are used within local networks. Addresses beginning with 192.168. are common in home network configurations, although they are not the only private range.
Public IP addresses can be used for communication over the wider internet, subject to allocation and routing. A syntactically valid address does not necessarily represent an active or publicly reachable device.
CGNAT (Carrier-Grade Network Address Translation) allows an internet provider to share public IPv4 addressing among multiple connections. The range 100.64.0.0/10 is designated as shared address space and is commonly associated with this arrangement.
If your PTCL or another Pakistani ISP connection shows an address within this shared range on the router’s WAN interface, CGNAT may be involved. The validator identifies the range, but it cannot confirm your ISP’s full network configuration.
Why Might an IP Address Be Invalid?
An address may fail validation because its format does not follow the required IPv4 or IPv6 syntax.
Common mistakes include:
- Using an IPv4 number greater than 255.
- Entering too many or too few IPv4 sections.
- Including spaces, a URL, or a port number.
- Using unsupported characters in an IPv6 address.
- Entering incorrect IPv6 colon separators or too many address groups.
For example, 256.10.20.30 is not a valid IPv4 address. Similarly, 2001:db8:::1 contains invalid IPv6 colon formatting.
Check the address for typing mistakes and remove any extra characters before validating again.
Does a Valid IP Address Mean the Device Is Online?
No. A valid IP address simply means that the entered text follows the required address format.
This validator does not establish whether the address belongs to an active device, responds to network requests, is currently allocated, or is reachable from your internet connection.
It also does not identify your current public IP address, determine an IP address’s physical location, detect your ISP, or test your internet speed.
Those functions require separate tools or network services.
Is It Safe to Validate an IP Address Here?
The IP Address Validator checks the address you enter directly in your browser. The validator itself does not transmit that entered value to a server or third-party lookup API.
However, normal website visits may involve hosting logs, analytics, cookies, or other services according to the website’s applicable privacy practices.
Avoid posting sensitive network configuration details publicly, particularly when sharing screenshots or troubleshooting reports.
When Should You Use This Tool?
An IP Address Validator is useful when checking an address copied from router settings, reviewing server configuration details, examining network documentation, or confirming that an address has been entered correctly.
It can also help distinguish familiar local-network addresses from shared or special-purpose ranges before further troubleshooting.
For address-format checks, use the validator above. For internet connectivity problems, remember that a correctly formatted IP address alone does not establish whether the connection is working.
Technical References
The address classifications and formatting conventions are based on recognized internet standards:
- IANA IPv4 Special-Purpose Address Registry
- IANA IPv6 Special-Purpose Address Registry
- RFC 5952 – A Recommendation for IPv6 Address Text Representation
NetTools Pakistan is an independent internet information and tools website. It is not an official PTCL or PTA service.