URL Encoder & Decoder

Encode and decode URLs or query parameters with support for UTF-8 component-level and full URI encoding on the same screen.

Processed 100% locally in your browser

1. URL Decoder

URL Encoded Input0 chars

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Decoded Plain Text / URL

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2. URL Encoder

Raw Text / URL Input0 chars

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URL Encoded Output

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Technical Documentation & Reference

Complete Guide to Percent-Encoding & URL Standards

Learn how Uniform Resource Identifiers (RFC 3986) escape reserved characters, the difference between encodeURI and encodeURIComponent, and UTF-8 query strings.

Percent-encoding (also known as URL encoding) is a mechanism defined in RFC 3986 for encoding information in a Uniform Resource Identifier (URI). URLs are restricted to a limited set of ASCII characters (alphanumeric characters, unreserved marks like hyphens, underscores, dots, and tildes). Characters outside this set—such as spaces, non-ASCII international letters, and reserved control characters (?, &, #, =)—must be converted into a percent sign followed by two hexadecimal digits representing their UTF-8 byte value.

Full URI vs. URI Component Encoding

A frequent source of broken web applications is confusing encodeURI with encodeURIComponent. Full URI encoding preserves protocol and routing syntax (https://, /, ?, #), intended for formatting an entire address. In contrast, Component encoding escapes every reserved delimiter, making it essential for query parameter values so that symbols like & and = inside user inputs don't corrupt the query string parser.

How to Use This Tool

Enter URL or Parameter String

Paste your raw URL, query parameter value, or encoded string into the input field.

Choose Component vs. Full URI Mode

Select Component Mode for individual query values, or Full URI Mode to preserve address delimiters.

Instant Encoding / Decoding

Toggle between Encode and Decode to see real-time percent-escaped or human-readable UTF-8 output.

Copy Converted Result

Copy the safe URL string with one click for use in API requests, links, or webhooks.

Key Features & Capabilities

RFC 3986 Strict Compliance

Accurately encodes all reserved characters and multi-byte UTF-8 sequences.

Dual Mode Support

Seamlessly switch between encodeURIComponent (parameters) and encodeURI (full links).

Real-Time Continuous Conversion

Outputs update instantly as you type with zero lag.

100% In-Browser Privacy

Encode proprietary API tokens and query params without server logging.

Frequently Asked Questions

What is percent-encoding in URLs?

Percent-encoding replaces characters that are not allowed in URLs with a "%" sign followed by two hexadecimal digits representing the UTF-8 byte value (e.g. space becomes "%20").

When should I use encodeURIComponent vs encodeURI?

Use encodeURIComponent when encoding individual query parameter values (like search terms or tokens) so delimiters like "&" and "=" are escaped. Use encodeURI when encoding a complete address where you want to keep the protocol (http://) and slashes intact.

Why does space sometimes encode as "+" instead of "%20"?

In standard RFC 3986 URL paths and modern APIs, spaces must be encoded as "%20". In legacy HTML form submissions (application/x-www-form-urlencoded), spaces were historically encoded as "+". Both represent a space.

Are my URLs sent across the internet to be encoded?

No. All encoding and decoding operations happen locally on your computer inside your browser.

Privacy & Security Guarantee

All data processing, AST syntax repairs, and cryptographic operations happen 100% locally inside your browser using native JavaScript and WebAssembly. No inputs, keys, or file payloads are ever transmitted to or stored on remote servers.