Base64 Encode / Decode - Free Online Base64 Converter

Encode text to Base64 or decode Base64 back to readable text. Supports file encoding for data URIs and JWT decoding. Everything runs in your browser — no data is sent anywhere.

What is Base64?

Base64 is a binary-to-text encoding scheme that represents binary data as ASCII characters. It uses 64 characters (A-Z, a-z, 0-9, +, /) to encode data, making it safe to transmit through text-based systems like email, JSON, and URLs.

Common uses

  • Data URIs — Embed images directly in HTML/CSS
  • JWT tokens — Header and payload are Base64-encoded
  • API payloads — Send binary data in JSON
  • Email attachments — MIME encoding uses Base64
  • Basic auth — HTTP Basic authentication header
  • Config files — Encode secrets in Kubernetes/Docker