When should I use encodeURIComponent vs encodeURI?

Use encodeURIComponent for individual query parameter values (such as a redirect_uri) because it encodes &, =, ?, and /. Use encodeURI when encoding a complete URL path while keeping protocol slashes intact.

Why do spaces sometimes appear as %20 and other times as +?

RFC 3986 path segments encode spaces as %20, whereas application/x-www-form-urlencoded query strings historically use +.

Can this decode double-encoded URLs?

Yes—click Decode and then swap output back to input to peel back multiple layers of percent-encoding.

Does this validate URL syntax?

When a full http/https URL is pasted, the query inspector parses protocol, host, pathname, and all search parameters cleanly.

Developer Tools100% Client-Side4.8 (530 ratings)

URL Encoder & Decoder

Built for web engineers and growth marketers debugging OAuth redirect URIs, UTM campaign links, and REST query parameters.

Component mode (encodeURIComponent)

Input URL or Query Value

Output

https%3A%2F%2Ftoolcix.com%2Ftools%2Fjson-formatter%2F%3Futm_source%3Dnewsletter%26q%3Dhello%20world

Query Key	Decoded Value
utm_source	newsletter
q	hello world

How to Use URL Encoder & Decoder

1Choose Component Mode (encodeURIComponent) or Full URI Mode (encodeURI).
2Paste any raw URL, encoded redirect string, or query parameter value.
3Click Encode or Decode to view instant output and parsed query parameters.
4Copy the clean encoded string in one click.

Key Features

Supports both encodeURIComponent and full-URI encodeURI modes
Automatic query string table parser showing each key & decoded value
Handles + to space query normalization cleanly
Zero network requests

Preventing Broken Redirects and Query Collisions

Passing unencoded ampersands, hashes, or nested callback URLs inside query parameters silently truncates parameter values and breaks OAuth flows. Understanding when to escape reserved delimiters saves hours of subtle debugging.

ToolCix pairs instant percent-encoding with a structured query-string breakdown table so you can verify every UTM tag, webhook parameter, and redirect target at a glance.

Debugging Encoded Payloads Together

If a decoded query parameter contains Base64 tokens or serialized JSON, jump straight to our Base64 Encoder & Decoder or JSON Formatter to inspect the inner payload cleanly.