How does Base64 decoding work?

Base64 decoding reverses the encoding process: each group of 4 Base64 characters is converted back to 3 bytes of binary data. The result is then interpreted as UTF-8 text.

What if my Base64 string is invalid?

If the input contains characters not in the Base64 alphabet or has incorrect padding, the decoder will show an error message. Valid Base64 uses A-Z, a-z, 0-9, +, /, and = for padding.

Can I decode Base64-encoded binary data?

This tool decodes to UTF-8 text. For binary data like images, use the Base64 to Image tool instead.

Base64 Decode

Decode Base64-encoded strings back to readable text.

$base64

lines

0 chars1 lines

$decoded[READY]

lines

0 chars1 lines

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FAQ

How does Base64 decoding work?: Base64 decoding reverses the encoding process: each group of 4 Base64 characters is converted back to 3 bytes of binary data. The result is then interpreted as UTF-8 text.
What if my Base64 string is invalid?: If the input contains characters not in the Base64 alphabet or has incorrect padding, the decoder will show an error message. Valid Base64 uses A-Z, a-z, 0-9, +, /, and = for padding.
Can I decode Base64-encoded binary data?: This tool decodes to UTF-8 text. For binary data like images, use the Base64 to Image tool instead.

Base64 decoding converts Base64-encoded text back to its original binary or text form. This tool decodes Base64 strings to UTF-8 text, correctly handling multi-byte characters. Useful for inspecting API responses, decoding embedded data, and reading Base64-encoded configuration values.