What is Base64? Encoding, Use Cases, and Decoding
You’ve probably seen “Base64” in development—image embedding, API payloads, and more. This article explains how it works, common use cases, and a common misconception. Try the Base64 tool to encode/decode on the spot.
What is Base64?
Base64 is an encoding scheme that converts binary data into text. Images and binary files can’t be sent as plain text, so Base64 uses 64 ASCII characters (A–Z, a–z, 0–9, +, /) to represent them. Roughly: 3 bytes (24 bits) become 4 characters.
Common Use Cases
- Data URI — Embed small images in HTML/CSS to reduce HTTP requests
- Basic auth — Encode “username:password” for the Authorization header
- APIs — Send binary data (e.g. images) in JSON payloads
- Email — MIME encoding for attachments
Important: It’s Not Encryption
Base64 is encoding, not encryption. Anyone can decode it. Don’t use it to “hide” passwords or API keys—use proper encryption (e.g. AES) for sensitive data.
How to Use
The Base64 tool runs in your browser—paste text and click Encode or Decode. Your data never leaves your device.
Summary
Base64 is a standard way to represent binary data as text. Use it for the right purposes, and remember: it does not protect secrets.