Guides

Practical guides to URL encoding.

Deep explanations of the things our tool handles for you. Aimed at developers and curious readers who want to understand why, not just how. Every guide is a complete standalone reference.

Reference

URL reserved characters — the complete table

Every character that needs URL encoding, what it becomes, and when you actually need to encode it.

By language

URL encoding in every programming language

The right function to use in JavaScript, Python, PHP, Java, Go, C#, Ruby, Rust, and shell.

Charsets

UTF-8 vs ASCII URL encoding

Why character sets matter, what UTF-8 does that ASCII can't, and how to fix garbled text.

How to

How to URL-encode query parameters

The right pattern for encoding query strings, plus the four common mistakes that break URLs.

Troubleshooting

Fix broken URL encoding

Seven symptoms of broken URL encoding, what causes each, and how to repair them.