Base64 Encoder & Decoder

About this tool

Base64 represents binary bytes as text using a restricted alphabet, making data easier to carry through JSON, email and URL-oriented systems. The Base64 Encoder and Decoder converts Unicode text safely and supports the URL-safe variant that replaces + and / and commonly omits padding.

Base64 is encoding, not encryption. Anyone with the value can decode it, and the encoded output is usually about one-third larger than the original bytes. Do not use it to hide passwords, tokens or personal information. This tool processes text in the browser; for JWT payload inspection, use the dedicated JWT Claims Decoder, which understands the token's dot-separated structure.

How to use it

1. Select Encode to convert readable text into Base64 or Decode to restore a Base64 value.
2. Enable URL-safe mode when the output will be used in a URL, cookie-like token or Base64URL format.
3. Paste the input and run the conversion.
4. Review decode errors for invalid characters, padding or incomplete input.
5. Copy the result, remembering that encoded sensitive data is still exposed data.

Useful ways to apply it

• Encoding small text values for APIs, test fixtures and data transport.
• Decoding a Base64 configuration value found in logs or documentation.
• Comparing standard Base64 with the URL-safe alphabet.
• Preparing a small data URI component after verifying the MIME requirements separately.
• Teaching why representation and encryption solve different problems.

Worked example

hello

aGVsbG8=

Edge cases to check

• Base64 is encoding, not encryption.
• URL-safe Base64 uses a different alphabet and often different padding conventions.
• Arbitrary binary data is not always meaningful as UTF-8 text.

Known limitations

Do not use Base64 to protect secrets; anyone can decode it.