Base64 Text Encoder & Decoder — Online Tool

What is Base64 Text Encoding?

Base64 is an encoding scheme that represents binary data using 64 printable ASCII characters (A–Z, a–z, 0–9, +, /). It doesn't encrypt — it just makes arbitrary bytes safe to transmit as text.

Why Use Base64 for Text?

HTTP headers, JSON payloads, and URLs can't safely carry arbitrary binary data. Base64 solves this by transforming any string into URL-safe or header-safe characters. It's the backbone of HTTP Basic Authentication (`Authorization: Basic dXNlcjpwYXNz`).

Key Benefits

• Encode any text string to Base64 instantly
• Decode any Base64 string back to plain text
• Handles Unicode (UTF-8) characters
• Supports large strings
• 100% client-side — nothing sent to server

How to Use Base64 Text Encoder

1. Paste or type your text in the input field
2. Switch between Encode and Decode modes
3. See the result instantly
4. Copy output to clipboard

Example Use Case

A developer debugging an API that uses HTTP Basic Auth needs to manually construct the Authorization header. Enter `username:password` → encode → get the Base64 string to paste in the header. Also useful for decoding JWT payloads (the middle part of a JWT is Base64-encoded JSON).

Tips

• Base64 is not encryption — do not use it to 'hide' sensitive data
• JWT middle section is Base64URL encoded (uses - and _ instead of + and /)
• btoa() and atob() are built-in browser Base64 functions
• For binary files, use the Base64 Image tool instead