Base64 Encoder / Decoder

Encode UTF-8 text to Base64 or decode Base64 back to text, locally.

Processed on this page. No uploads. Your input is not saved.

Up to 100,000 characters. Text is encoded as UTF-8; file bytes are not supported.

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How to use

Encode plain text as UTF-8 Base64, or decode standard/Base64URL text back to UTF-8. Whitespace and missing padding are accepted when valid. Invalid Base64 and invalid UTF-8 are rejected. This tool handles text, not arbitrary file bytes.

Encode or inspect a Base64 text value

Paste plain text to encode it as UTF-8 Base64, or paste valid Base64 / Base64URL text to decode it. Copy the result only after checking which representation the receiving API expects.

Example and expected result

“Hello” encodes as SGVsbG8=. The unpadded form SGVsbG8 also decodes to “Hello”. This tool handles UTF-8 text, not arbitrary binary files; invalid UTF-8 is reported instead of being replaced silently.