How Base64 & URL Encoder/Decoder Works and How to Use It
A fast and secure Base64 and URL encoder/decoder tool for developers and everyday users. Convert strings in real-time, copy effortlessly, and handle Unicode smoothly.
What is Base64 Encoding/Decoding?
Base64 is an encoding scheme that converts 8-bit binary data into a string made up only of common ASCII characters that aren't affected by character-set issues. It's commonly used to embed image data, send email attachments, and lightly obfuscate data. (This tool fully supports Unicode characters such as Korean and emojis.)
What is URL (URI) Encoding/Decoding?
URL encoding converts characters that can't appear directly in a URL — such as spaces, special symbols, or non-ASCII characters like Korean — into a safe transmission format (e.g. %20, %EA%B0%80). It's especially handy when building query strings.
100% Client-Side (Local) Processing
Every text and data conversion in this tool happens entirely in your browser's memory — nothing is sent to any server. That makes it safe to use even with sensitive data or credentials.
Frequently Asked Questions
Q. What is Base64 used for?
Safely transporting binary data as text — image/file attachments, JWT tokens, data URLs.
Q. Why URL-encode?
URLs can't carry raw special characters (spaces, &, =, Korean). Percent encoding (e.g. %20) makes them safe.
Q. Korean characters break — what now?
The tool defaults to UTF-8. Legacy encodings like EUC-KR need separate conversion. Malformed input is highlighted.
Q. How large can the input be?
Browser memory limits — several MB is fine. Large videos as Base64 are impractical.
Q. Does my data leave the browser?
No. Everything runs locally — safe for JWT or API key inspection.
Q. URL-safe Base64 vs standard?
URL-safe uses - and _ instead of + and /. Used in JWTs. The tool supports both.
