What characters does URL encoding escape?

All characters except A-Z, a-z, 0-9, and - _ . ~ are percent-encoded. For example, spaces become %20 and & becomes %26.

What is the difference between encodeURI and encodeURIComponent?

encodeURI preserves URL structure characters like : / ? # while encodeURIComponent encodes everything except unreserved characters. Use encodeURIComponent for individual parameter values.

Why do I need URL encoding?

URLs have special characters with reserved meanings (? starts query, & separates params, = assigns values). Encoding ensures your data does not break the URL structure.

URL Encode

Encoding Tools

Encode text for safe use in URLs

By DevToolHQ teamUpdated 2026-04-15100% client-sideMethodology

100% client-side processing

Input Text

About URL Encode

Percent-encoding (also called URL encoding) converts characters that have special meaning in URLs — or that are not safe to include in URLs — into a % followed by their two-digit hexadecimal UTF-8 byte values. A space becomes %20, an ampersand becomes %26, a forward slash becomes %2F. This tool uses encodeURIComponent behavior: it encodes everything except the unreserved characters A–Z, a–z, 0–9, and - _ . ~ . This is the correct function to use when encoding individual query parameter values or path segments. Do not use it on an entire URL — that would encode the : and / characters that define the URL structure. The most common use case is constructing API requests with dynamic query parameters. If a user searches for "C++ tutorial", the parameter value needs to be encoded as C%2B%2B%20tutorial before being appended to the URL. Failing to encode parameters causes silent data corruption or broken requests when the value contains &, =, or # characters. Application/x-www-form-urlencoded format (used by HTML form submissions) uses a slight variant where spaces are encoded as + rather than %20 — this tool uses the %20 standard.