Security
Base64 Encoder & Decoder
Encode or decode text to Base64 ASCII strings with full multi-byte Unicode UTF-8 handling.
Encoding Is Not Encryption
Base64 transforms bytes into a text-safe alphabet of 64 characters; anyone can reverse it instantly. Encoding a password or API key in Base64 provides exactly zero secrecy — yet "Base64-encoded credentials" appear in real breaches constantly, because the output looks opaque.
Its legitimate jobs: embedding small images or fonts in CSS, carrying binary payloads through JSON or email (MIME), and JWT segments. Output grows by roughly 33% (3 bytes become 4 characters), and padding "=" characters are part of the spec, not corruption.
Base64 Is Encoding, Not Encryption
Base64 represents binary data using 64 printable characters so it can travel through systems built for text. Anyone can decode it instantly, so it provides no secrecy. Encoded data is about one third larger than the original.
Unicode needs care: text is first converted to UTF-8 bytes, which is why accented characters and emoji decode correctly here but fail in tools that handle only ASCII. URL-safe Base64 replaces + and / with - and _, and the trailing = padding may be dropped.
How It Generates Output
- Uses TextEncoder and TextDecoder to handle emojis and special characters safely.
Example Output
Common Questions
Is Base64 encryption?
No. It is a text encoding format, not an encryption cipher. It provides zero security.
Why does Base64 add "=" padding?
Base64 encodes 3 input bytes into 4 characters. When the input length is not a multiple of 3, the final chunk is padded with "=" signs so decoders can reconstruct the exact original byte length.
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