Base64 & URL Encoder / Decoder
About the Base64 & URL Transformer
Encode and decode Base64, escape and unescape URL components, and convert text case — all in one developer utility. It is built for quick, everyday tasks like inspecting a JWT segment, fixing a broken query string, or preparing a data snippet. Every transform runs locally in your browser. Your input is never sent to a server, which makes it safe for tokens, keys, and other sensitive strings.
This tool works in your browser: the files and text you use are processed on your device and are not uploaded.
How to use it
- Pick a mode: Base64, URL, or case conversion.
- Paste or type your text into the input box.
- Copy the transformed result from the output box.
Frequently asked questions
Is it safe to paste sensitive data here?
Yes. All encoding and decoding happens entirely in your browser with JavaScript — nothing you type is uploaded, logged, or stored, so tokens and secrets never leave your machine.
What is the difference between Base64 encoding and encryption?
Base64 is an encoding, not encryption. It simply represents binary or text data using 64 printable characters so it can travel safely through text-only channels. Anyone can decode it — never use Base64 to hide secrets.
When should I URL-encode text?
Whenever text goes into a URL query string or path and contains characters like spaces, &, ?, =, or non-ASCII letters. Encoding turns them into %-escapes so the URL is parsed correctly instead of breaking at those characters.
Why did decoding fail or produce garbled text?
Base64 decoding fails if the input is not valid Base64 (wrong length or stray characters), and URL decoding fails on a lone % not followed by two hex digits. Check that you copied the whole string and are using the matching decode mode.