Base64 Encode/Decode

Encode and decode text with Base64

Runs locally in your browser

How it works

Encodes plain text to Base64 and decodes Base64 back to readable text, supporting UTF-8 characters including emoji and non-Latin scripts.

Who it's for: Developers handling Basic Auth headers, data URIs, embedded payloads, and legacy APIs that expect Base64 strings

Encodes arbitrary UTF-8 text into a Base64 string safe for HTTP headers and JSON fields.

Decodes Base64 back to the original text when the input is valid.

Runs entirely client-side with no server round trip.

Enter or paste your text in the input field.
Click Encode to produce a Base64 string, or Decode when starting from Base64.
Copy the result for use in Authorization headers, config files, or test fixtures.
If decoding fails, confirm padding, line breaks, and that the string is standard Base64 (not Base64URL unless adjusted).

Base64 increases size by roughly 33%—use it for transport encoding, not compression.
JWT segments use Base64URL (no padding, URL-safe alphabet)—this tool uses standard Base64 for general text.
Line-wrapped PEM blocks may need newlines removed before decoding.

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