URL Encoder & Query Parser
A tool for URL encoding (encodeURIComponent / encodeURI) and decoding, plus extracting, editing, and regenerating a URL's query parameters (?key=value) as a table. Everything runs entirely in your browser.
encodeURIComponent is best for encoding a single value, like a query parameter. encodeURI is best for encoding a whole URL while preserving reserved characters (:/?# etc).
How to use
- On the "Encode / Decode" tab, enter text and choose encodeURIComponent (best for encoding a single value) or encodeURI (best for encoding a whole URL) to convert it.
- On the "Parse Query Parameters" tab, enter a URL and click "Parse" to automatically extract the base URL and query parameters.
- You can directly edit the extracted parameters' keys and values, add a new one with "Add parameter", or remove one with the × button.
- Your edits are reflected in the "Regenerated URL" field in real time, ready to use via "Copy to clipboard".
About this tool
This tool encodes and decodes Japanese text and symbols in URLs, and lets you inspect and edit query parameters, all in your browser. It's useful when building an API request URL or figuring out what the parameters in a long URL mean.
encodeURIComponent and encodeURI differ in which characters they encode. Use encodeURIComponent when you want to encode an entire string, such as a query parameter value; use encodeURI when you want to encode a whole URL while preserving structural characters like ":", "/", "?", and "#".
The query parameter parsing feature uses URLSearchParams to convert a "?key1=value1&key2=value2" string into a table, and immediately regenerates a new URL as you add, edit, or remove keys and values.
Frequently asked questions
Should I use encodeURIComponent or encodeURI?
Use encodeURIComponent when encoding a single string you'll embed as part of a URL, such as a query parameter value. Use encodeURI when encoding an already-complete URL, since it preserves structural characters (:/?# etc.) without encoding them.
Can it handle query parameters with the same key repeated?
Yes. When the same key appears multiple times, like "tag=a&tag=b", each occurrence is shown and editable as a separate row.
What happens to the hash (the fragment after #)?
It's kept separate from the query parameters and appended back to the end when the URL is regenerated.
Is my input URL sent to a server?
No. Parsing, editing, and regenerating URLs, as well as encoding and decoding, all happen entirely with JavaScript in your browser.