Free Tools

Online Web and Network Tools: URL and UTM, Subnet Calculator, HTTP Status Codes, Browser Info

Choose a tab below. Each tool also has its own page. These tools only work on what you type; they do not look up IPs or domains with outside services (WHOIS, DNS and speed tests need a server).

URL Parser, Query Parameter Editor, Tracking Remover, UTM Link Builder and URL Encoder

Paste a link to see what is inside it. Links people send often carry tracking parameters (utm_, fbclid, gclid) that say where you came from; "Remove tracking" cuts them out and the link still works. The second part builds campaign links and the third encodes and decodes text for URLs.

Build a campaign (UTM) link

Percent-encode / decode

Subnet and CIDR Calculator for IPv4 and IPv6: Network, Broadcast, Usable Range and Subnet Splitting

Type an address like 192.168.1.10/24, 10.0.0.0 255.255.255.0 or an IPv6 prefix such as 2001:db8::/32. This is pure arithmetic: it does not look up who owns an address (that needs an outside service).

HTTP Status Codes: Every Common Code (200, 301, 404, 500) with Meaning and When You See It, Searchable

Type a number (such as 40) or a word (such as redirect or timeout) to filter. The first digit is the class: 2 success, 3 redirect, 4 the client made a mistake, 5 the server failed.

CodeNameMeaningWhen you see it

What Websites Can See About Your Browser, and a User-Agent Parser

The table shows what every site can read the moment you open a page (this tool only reads it and shows it to you, and sends nothing). Combined, these values can tell you apart from other people, which is called a browser fingerprint. The parser box works on any User-Agent.

This browser

Parsed

Browser
Rendering engine
Operating system
Device type
Bot / program

FAQ

What is tracking in a link, and does the link still work without it?

Parameters such as utm_source, fbclid and gclid tell the destination which ad or post you came from; they do not change the page. Without them the link works the same, except on the rare site that reuses those names for something else.

How should UTM tags be set?

Always include source, medium and campaign, keep them lowercase and name them consistently (facebook, not sometimes Facebook and sometimes fb). Do not put UTM tags on links inside your own site, as they overwrite where the visitor really came from.

What is the difference between encodeURI and encodeURIComponent?

encodeURI is for a whole link and keeps structural characters such as / ? &. encodeURIComponent is for one piece (such as a parameter value) and encodes those characters too.

How many IPs are in a /24?

A /24 has 256 addresses, 254 usable (minus network and broadcast), with subnet mask 255.255.255.0.

How are /31 and /32 different?

A /31 is for a point-to-point link (RFC 3021): both addresses are usable and there is no broadcast. A /32 is a single host.

Does IPv6 have no broadcast?

Right. IPv6 uses multicast instead, and the standard subnet size is /64. The tool shows the first to last address of the prefix you enter.

What is the difference between 301 and 302?

301 is a permanent move, so search engines transfer ranking to the new address; 302 is temporary and ranking stays put. For a permanent domain move use 301 (or 308 if the request method must be kept).

What is the difference between 401 and 403?

401 means you are not authenticated (no token, or a wrong one); 403 means you are authenticated but not allowed.

What is the difference between 404 and 410?

404 means not found and may come back; 410 means removed on purpose for good, and search engines tend to drop the page faster.

How do 502, 503 and 504 differ?

502: a proxy got a bad answer from the back end. 503: the service is temporarily unavailable (maintenance or overload). 504: the proxy waited too long for the back end.

What is a browser fingerprint?

A combination of many small browser details (screen size, fonts, graphics card, language and so on) that is almost unique to one person and can be used to follow you across sites even after you clear cookies.

How can I reduce tracking?

Use a browser with fingerprint protection (such as Firefox with strict tracking protection, or Brave) and fewer extensions. Turning on Global Privacy Control tells sites you do not consent to the sale of your data, but it is not a technical defence.

Why does the User-Agent not match reality?

Browsers trim details for privacy and also list other browsers' names for compatibility, so Edge says Chrome and Safari too. The parser therefore tests the most specific rules first.