IP address validator
Validate one IPv4 or IPv6 address per line and export the valid entries.
- 1Add input
- 2Review and run
- 3Get your result
Tool input and files are processed in this browser without being uploaded.
Before you start
Paste a list of IP addresses or open a UTF-8 text file. The tool checks each nonblank line as a complete address, keeps source line numbers for errors, and exports valid entries as plain text. It checks syntax, not reachability or ownership.
How to use this tool
- Paste one address per line or choose a UTF-8 .txt file.
- Review the input count and invalid count before running; blank lines are ignored.
- Select “Validate IP addresses”. Check invalid line numbers, copy or download valid addresses, or download the complete JSON report.
Supported inputs and limits
Up to 10,000 nonblank lines; one IPv4 or IPv6 address per line. Blank lines are ignored. CIDR prefixes, CSV rows and zone identifiers are not accepted.
Input and files stay in your browser. Validation does not query DNS, geolocation, assignment or network reachability.
Worked example
Example input
127.0.0.1 ::1 999.1.1.1
Example options
{}Example output
{
"total": 3,
"valid": 2,
"invalid": 1,
"ipv4": 1,
"ipv6": 1,
"rows": [
{
"line": 1,
"address": "127.0.0.1",
"valid": true,
"version": 4,
"reason": null
},
{
"line": 2,
"address": "::1",
"valid": true,
"version": 6,
"reason": null
},
{
"line": 3,
"address": "999.1.1.1",
"valid": false,
"version": null,
"reason": "range"
}
]
}When something does not work
If a line is invalid, use its displayed original line number to correct the source. For CSV, extract the address column first.
Frequently asked questions
Does a valid address mean the host is reachable?
No. A valid result means only that the line parses as an IPv4 or IPv6 address. The tool makes no network request.
What happens to blank lines and invalid entries?
Blank lines are ignored. Invalid nonblank lines remain in the JSON report with their original physical line number; they are excluded from valid-addresses.txt.
Can I paste CIDRs or CSV columns?
This tool expects one complete address on each line. CIDR prefixes and comma-separated rows are marked invalid; prepare a one-column text list first.
Documentation & further reading
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