Before an address goes into a firewall rule, an allowlist, or a stored audit record, it should be checked.
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IP Address Tools
Ip
Free · API · MCPToolYour platform
Use IP Address Tools three ways
The free IP Address Tools on this page works in your browser. The same workflow is available via REST API for apps and via MCP for Cursor, Claude, and other agents — one API key, one plan, one quota. This tool is part of the developer-apis module under Developer Tools.
- Free in browserUse IP Address Tools here — no account required.
- REST APICall from your server with
X-Api-Key. - MCP for agentsConnect Cursor or Claude to ToolYour MCP with the same key.
- 1. Get an API keySign in and open Dashboard → API Keys (works for REST and MCP).
- 2. Call or connectUse the REST API from your server, or paste the MCP URL into your agent config.
- 3. Same qualityOutput matches the free web tool across all three surfaces.
What is IP Address Tools?
Before an address goes into a firewall rule, an allowlist, or a stored audit record, it should be checked. This IP address tool validates the string, reports whether it is IPv4 or IPv6, and flags the two classifications that matter most in practice: whether the address falls in a private range and whether it is loopback.
Validation is genuine for IPv4 — each of the four octets is range-checked, so 192.168.1.300 is rejected rather than accepted as a plausible-looking string, and the 10, 172.16 to 172.31, 192.168, and 127 ranges are recognised as private or loopback. IPv6 handling is lighter: the format is recognised and unique-local and loopback forms are flagged, but full canonicalisation is not performed. There is no geolocation, no ASN owner, no reverse DNS, and no reputation or threat data — those need dedicated intelligence services. For the other half of a log line, User Agent Parser classifies the client.
Browser use is free and needs no signup. The same job runs over REST at POST https://api.toolyour.com/api/v1/developer-apis/ip-address-tools and over MCP at https://api.toolyour.com/mcp — one API key, one shared monthly credit pool, 1 credit per successful call.
What are common questions about IP Address Tools?
Does it include geolocation?
No. There is no country, city, ASN, reverse DNS, or reputation data. This is local validation and range classification only.
Is IPv6 fully supported?
Partially. IPv6 format is recognised and loopback and unique-local addresses are flagged, but full canonicalisation and range analysis are not performed.
Are IPv4 octets range-checked?
Yes. Any octet above 255 is rejected, so malformed addresses that merely look correct do not pass validation.
What are the key features of IP Address Tools?
Real IPv4 validation
Every octet is range-checked rather than pattern-matched, so 300 is rejected.
Private and loopback flags
RFC 1918 ranges and localhost are identified, which matters for allowlists.
No external lookups
Purely local classification — nothing is queried and nothing is logged upstream.
How do you use IP Address Tools?
Paste the address
A literal IPv4 or IPv6 address from a log, config, or ticket.
Check the classification
Confirm the version and whether it is private or loopback.
Apply it safely
Write the firewall rule or allowlist entry once the address is confirmed valid.
Why private-range detection matters
Two situations make the private flag more than trivia. Allowlists — an entry containing a private address is almost always a mistake, because it either never matches production traffic or matches every internal caller. Catching it before deployment avoids a rule that appears to work and does nothing.
Server-side request forgery — when your service fetches a URL supplied by a user, resolving to 127.0.0.1, 169.254.169.254, or a 10-range address is the classic path to internal metadata and admin endpoints. Range classification is one of the checks a URL-fetching feature needs, though a complete defence also handles DNS rebinding and redirect chains.
Reading an access log line by line
A log entry usually carries three things worth checking separately: the address, the client string, and the timestamp. Classify the address here, run the client string through User Agent Parser, and normalise the time with Timestamp Converter so events from different systems line up.
Remember that a logged address may belong to a proxy or CDN rather than the real client. If your infrastructure sets forwarding headers, the meaningful address is in there — and it is client-supplied unless your edge overwrites it, so treat it accordingly.
Which HTTP / auth helper tools sit in this cluster?
Where do you browse more developer tools tools?
- Developer Tools tools
Browse the full Developer Tools category on ToolYour.
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Build UTM links, check ads copy limits, QA email subjects, and calculate ROAS/CPC/CTR — free in the browser; R
- Security Tools tools
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