Base64 Encode & Decode
Convert any text to Base64 encoding or decode Base64 strings back to readable text. Supports UTF-8 characters. All processing happens locally in your browser for maximum privacy.
How to Use the Base64 Encoder & Decoder
Select Encode → Base64 to convert plain text into Base64, or Decode ← Base64 to convert a Base64 string back to readable text. Type or paste your input into the left panel, and the result appears instantly in the right panel.
The encoder fully supports UTF-8, meaning you can encode text containing accented characters, emoji, Chinese, Arabic, or any other Unicode content. The decoder handles both standard Base64 and URL-safe variants. If you provide invalid Base64, the tool shows a clear error message instead of silent garbage output.
Click the Copy button in the output panel to copy the result to your clipboard. Switching between Encode and Decode modes clears the input so you start fresh.
What Is Base64?
Base64 is an encoding scheme that represents binary data using only 64 printable ASCII characters: A–Z, a–z, 0–9, +, and /. A padding character (=) is used to ensure the output length is a multiple of 4.
Base64 was designed to safely transmit binary data over systems that were originally built to handle text. Because raw binary bytes can include control characters and null bytes that may be misinterpreted by text-based protocols, encoding them as printable ASCII characters sidesteps the problem entirely.
Common use cases for Base64 include:
- Email attachments: The MIME standard uses Base64 to encode binary attachments so they can travel through email systems.
- Data URIs: Inline images in HTML/CSS use Base64 to embed binary image data directly in the document.
- JWT tokens: JSON Web Tokens use URL-safe Base64 to encode their header and payload sections.
- API credentials: HTTP Basic Authentication encodes username:password as Base64 in the Authorization header.
- Cryptographic keys: Public and private keys are commonly stored and transmitted in Base64-encoded PEM format.
Important: Base64 is an encoding, not encryption. It provides no security by itself — encoded data can be decoded by anyone who sees it. Do not use Base64 to protect sensitive information.
Privacy
All encoding and decoding is performed locally in your browser using the built-in TextEncoder, TextDecoder, btoa(), and atob() APIs. Your data never leaves your device.