Base64 explained: what it is and when to use it

Base64 is one of those things every developer meets but few explain well. Here's the plain version: it converts binary data into safe text characters.

Why it exists

Emails, JSON, URLs and many protocols only handle text. But images, files and encrypted data are binary. Base64 encodes that binary as letters and numbers — so it can travel through text-only systems.

Where you see it

• Email attachments (MIME)
• Data URIs in HTML/CSS: data:image/png;base64,...
• API tokens and JWTs
• Storing binary in JSON

How to encode/decode

Our Base64 Encoder handles both directions, Unicode-safe (emoji work too). Paste, click Encode or Decode, copy.

Note

Base64 is not encryption — anyone can decode it. Use it for transport, not security.