Developer

What is Base64 Encoding (and When to Use It)

June 5, 2026 · By Toolzy Team

What it does

Base64 encodes binary data (like images) into a set of 64 safe ASCII characters, so it can travel through systems built for text, email, JSON, data URIs.

It is not encryption

Base64 is fully reversible and offers zero security. Never use it to hide passwords.

Good use cases

  • Embedding small images directly in CSS/HTML with data URIs
  • Encoding binary in JSON payloads
  • Basic auth headers

The trade-off

Base64 increases size by ~33%. Use it only for small assets. Try our Base64 Encode/Decode tools to experiment.

Try the tool

Base64 Encode →

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