Base64 Decoded: What Actually Happens When You Hit 'Encode'

Base64 is not encryption — it's encoding. If you paste Hello into a Base64 encoder and get SGVsbG8=, no secret key was used. The algorithm just translates binary data into 64 printable ASCII characters so it can travel through text-only channels like email, JSON, and URLs.

The Algorithm in Plain English

Take your input bytes and group them in sets of 3 (24 bits total).

Split those 24 bits into four 6-bit chunks.

Each 6-bit value (0-63) maps to one character in the Base64 alphabet: A-Z, a-z, 0-9, +, /.

Base64 Decoded: What Actually Happens When You Hit 'Encode'

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Base64 encoding visualizer