Base64 Decoder

Decode Base64 strings back into readable text.

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How to Use

  1. 1Paste a Base64 string into the input box.
  2. 2Click "Decode".
  3. 3Copy the decoded text.

Features

  • Full Unicode support
  • Clear error message for invalid Base64
  • Copy result with one click

Example

Input

SGVsbG8sIFBEVXRpbGl0aWVzIQ==

Output

Hello, PDUtilities!

Convert Base64-encoded strings back to their original text instantly in your browser, with clear error handling for invalid input.

Turn Base64 back into text

Paste a Base64 string and get the original text. Decoding is the quickest way to see what is inside an encoded config value, an HTTP Basic auth header, an email source, or a JWT payload. The result is decoded as UTF-8, so non-English text and emoji come out correctly.

Recognising Base64

  • Only letters, digits, + and /, often ending in one or two = signs.
  • Length is a multiple of four, including the padding.
  • Strings starting with eyJ are almost always Base64-encoded JSON, because that is how {" encodes. JWTs start this way.

Why decoding might fail

  • URL-safe Base64. Some systems, including JWTs, use - and _ instead of + and /. Replace - with + and _ with / and decode again. Missing = padding and line breaks are handled for you.
  • Extra characters such as quotes, a Basic prefix from an auth header, or a data:…;base64, prefix. Paste only the encoded part.
  • Binary data. If the original was an image or a zip file, the decoded result is not readable text.
  • A truncated string copied incompletely.

Decoding a token? Remember a JWT has three dot-separated parts. Decode the first two separately; the third is a signature and is not readable. Everything is decoded locally, so secrets you paste stay on your device.

Frequently Asked Questions