Developer Tools

Online URL Encoder & Decoder

Safely escape special characters, spaces, and Unicode glyphs into standard percent-encoded format, or decode percent-encoded URLs back to readable text.

Input Text / URL
Processed Output

How to Encode and Decode URLs

1

Input Your String

Paste the raw query parameter or percent-encoded URL string into the left editor pane.

2

Choose Encode or Decode

Click Encode to transform special characters into %XX hex sequences, or Decode to restore text.

3

Copy or Swap

Copy your processed output or click Swap to reverse the transformation workflow easily.

Features & Benefits

Strict RFC 3986 Standards

Guarantees uniform adherence to international Internet Engineering Task Force URI syntax standards.

Helpful Error Diagnostics

Flags malformed hexadecimal sequences when decoding broken or incomplete URLs.

Two Flexible Modes

Component mode encodes query values (including & and =), while Full URL mode preserves core protocol and domain delimiters.

Common Percent-Encoded Sequences

Space Character

%20
Represents an ASCII space inside URLs to prevent link truncation in chat applications and emails.

Ampersand & Equals

& → %26, = → %3D
Safely passes nested parameters without colliding with standard HTTP query separators.

Question Mark & Hash

? → %3F, # → %23
Prevents characters from prematurely initiating new query strings or client hash anchors.

Frequently Asked Questions

Use Component mode when encoding a specific query parameter value (e.g. search?query=val) where characters like /, ?, &, and = must be escaped. Use Full URL mode when encoding a complete link (e.g. https://site.com/path with space) where the protocol and slashes must remain intact.
This error occurs when a percent sign (%) in the input string is not followed by two valid hexadecimal digits (0–9, A–F), or if a multi-byte UTF-8 sequence is incomplete.

Related Tools

The Architecture of Percent-Encoding (RFC 3986)

Uniform Resource Identifiers (URIs) are constrained to a restricted subset of the US-ASCII character repertoire. Characters permitted in URIs are divided into reserved and unreserved characters.

Unreserved characters include uppercase and lowercase English letters, decimal digits, and four special punctuation marks: hyphens (-), underscores (_), periods (.), and tildes (~). All other characters—including whitespace, non-ASCII Unicode characters, and reserved structural delimiters—must undergo percent-encoding when included in arbitrary component slots.

How Percent Encoding Operates

During the encoding process, each non-conforming character is first converted into its UTF-8 octet byte sequence. Each byte is then represented by a percent character (%) followed by a two-digit hexadecimal representation of that byte value. For instance, the UTF-8 byte for an ASCII space is decimal 32, which converts to hexadecimal 20, yielding %20.