URL Parser

How to use URL Parser

1. Paste or drop a URL into URL, or click Try an example.
2. For a relative URL such as ../img/logo.png or ?page=2, enter a Base URL to resolve it against.
3. Read the Parts panel (origin, protocol, username, password, host, port, path, query and hash) and the decoded Path segments. Each value has its own copy button; the password stays hidden until you click Show.
4. Under Query parameters, edit keys and values, remove rows or use + Add parameter. The Rebuilt URL updates as you type: copy it, send it to another tool with Send to…, or click Use as input to parse it again.

How it works

The URL is parsed with your browser’s built-in URL API, which implements the WHATWG URL Standard, so you see exactly what fetch() and links would use: the host is lower-cased and converted to punycode, default ports are dropped, . and .. path segments are resolved, and characters that need escaping are percent-encoded. If parsing fails and a base URL is given, the input is resolved relative to that base, the same way a browser resolves a link on a page.

Path segments, the username, the password and the hash are shown percent-decoded. An internationalised host name in punycode (xn--…) is also decoded to Unicode with an RFC 3492 decoder. When the port is omitted, the default for http, https, ws, wss or ftp is shown.

Query parameters are read with URLSearchParams, which decodes %XX escapes and turns + into a space. Order and repeated keys are kept. The rebuilt URL serialises the rows the same way, so spaces become + and other reserved characters are percent-encoded; rows with both key and value empty are left out.

Limits

• Input longer than 100,000 characters is rejected.
• A relative URL can’t be parsed without a base URL, and a base must itself be an absolute URL with a scheme.
• The rebuilt URL re-encodes the whole query string with URLSearchParams rules, so it can differ from the original (for example %20 becomes +) even if you change nothing.
• Only the query string can be edited; change other parts in the URL box.
• The tool only parses the URL. It doesn’t check that the host exists or that the page can be reached.

Privacy

Parsing runs entirely in your browser; nothing is requested or uploaded, and the site’s Content Security Policy blocks requests to other servers. Nothing is stored. Copy share link puts the URL and base URL (including any username and password in them) into the link’s # fragment, which browsers don’t send to servers, but anyone you give the link to can read it. Query edits aren’t included. Send to… hands the rebuilt URL over through this tab’s session storage, and it is removed as soon as the receiving tool reads it.

Frequently asked questions

Why does the parsed URL look different from what I pasted?

The browser normalises URLs: it lower-cases the scheme and host, converts international host names to punycode, removes a default port such as :443, resolves . and .. in the path and percent-encodes characters such as spaces. The Full URL shows the result.

How do I parse a relative URL?

Enter the page it appears on as the Base URL, for example https://example.com/docs/. The relative URL is then resolved as a browser would resolve a link on that page.

Why did %20 turn into + in the rebuilt URL?

The query is rebuilt with URLSearchParams, which writes spaces as + (the form-encoding convention). Servers that decode query strings as forms treat both the same.

What happens to repeated parameters like tag=a&tag=b?

Each occurrence gets its own row, in the original order, and the rebuilt URL keeps them all.