Base64 Encode / Decode
Encode or decode Base64 strings with full UTF-8 support.
Runs in your browser All processing happens locally. Your data never leaves this device.
Overview
Base64 is an encoding that maps arbitrary bytes to a 64-character ASCII alphabet
(A–Z, a–z, 0–9, +, /). It lets you carry binary data through channels
that only reliably handle text — data URIs, JSON, email, and HTTP headers.
How to use
- Choose Encode to turn text into Base64, or Decode to reverse it.
- Type or paste your input. The result updates instantly.
- Copy the output.
Examples
Hello, world→SGVsbG8sIHdvcmxkSGVsbG8sIHdvcmxk→Hello, world
Notes
Base64 is encoding, not encryption — it provides no confidentiality. Anyone can decode it. For secrets, use real cryptography.
FAQ
- Is my data sent to a server?
- No. Base64 encoding and decoding happen entirely in your browser using the built-in TextEncoder and btoa/atob APIs. Nothing is uploaded.
- Does this support Unicode and emoji?
- Yes. Input is encoded as UTF-8 before Base64 conversion, so multi-byte characters and emoji round-trip correctly.
- What is Base64 used for?
- Base64 represents binary data as ASCII text. It is commonly used in data URIs, email attachments (MIME), Basic auth headers, and embedding small assets in HTML or CSS.