URL Encoder / Decoder

URL encoding converts characters that are not allowed or have special meaning in a URL into a % followed by two hexadecimal digits. For example, a space becomes %20 and & becomes %26. This ensures the URL is valid and can be transmitted safely over the internet.

encodeURIComponent encodes almost all special characters including :, /, ?, #, and @, making it ideal for encoding individual query-string values or path segments. encodeURI preserves those structural characters because it expects a full URL — use it to encode a complete URL without breaking its structure.

%20 is the percent-encoded representation of a space character (ASCII code 32, hex 20). Because spaces are not allowed in URLs, they must be encoded. Some systems use + instead of %20 in query strings (application/x-www-form-urlencoded), but %20 is correct for path segments and is universally understood.

RFC 3986 defines unreserved characters that never need encoding: uppercase and lowercase letters (A–Z, a–z), digits (0–9), hyphen (-), underscore (_), period (.), and tilde (~). All other characters should be percent-encoded when used in a URL path or query string.

A query string is the part of a URL after the ? character, containing key=value pairs separated by &. Each key and value should be encoded with encodeURIComponent to ensure special characters like &, =, and + don't break the structure. This tool's Query String tab builds or parses these automatically.

This usually happens when non-UTF-8 percent-encoded sequences are decoded as UTF-8. Older systems sometimes use Latin-1 or other encodings. Try decoding with a different encoding assumption, or check the original encoding of the source. All modern systems should use UTF-8 for URL encoding.

URL encoding (percent encoding) replaces unsafe characters with % + hex codes and is specifically designed for URLs. Base64 encodes arbitrary binary data as alphanumeric text and is used for embedding binary data in text formats like JSON or HTML. They serve different purposes — use URL encoding for URLs and Base64 for binary data.

Yes — switch to the Batch tab, paste one URL or string per line, choose an operation, and every entry is encoded or decoded simultaneously. The results table shows the original and transformed values side by side, and you can copy all results with one click.