Free Online Base64 Encoder / Decoder

Encode any text string to Base64 or decode a Base64 string back to plain text. Full Unicode support — works with emojis, accented characters, and multi-byte scripts.

Plain Text

Base64 Output

What is Base64?

Base64 is an encoding scheme that converts binary data — or any text — into a string of 64 printable ASCII characters (A–Z, a–z, 0–9, +, /). It is widely used wherever binary data needs to be safely transmitted through text-based channels such as HTTP headers, JSON payloads, or email attachments.

Base64 is not encryption. The original data can be recovered by anyone with the encoded string. Use it for encoding, not for securing sensitive information.

How to Use the Base64 Tool

Select the mode — Encode to convert text → Base64, or Decode to convert Base64 → text.
Paste your input into the left field.
Click Encode / Decode to process. The result appears on the right.
Use Swap to flip the output back into the input field and switch modes — handy for round-trip testing.

Common Use Cases

API authentication: Basic Auth credentials are sent as Base64-encoded username:password in the Authorization header.
JWT tokens: Decode the header and payload sections of a JWT to inspect claims without a dedicated library.
Image embedding: Inline small images in CSS or HTML as Base64 data URIs to reduce HTTP requests.
Email attachments: MIME encodes binary attachments as Base64 so they can travel safely through mail servers.