Convert any text to leet speak (1337) with basic, advanced, or maximum substitution levels. Reverse leet to plain text with best-effort decoding.
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Quick answers to common questions
Leet speak (1337 speak or leetspeak) is an alternative alphabet used primarily in internet culture where standard letters are replaced with numbers or symbols that resemble them visually. The name comes from 'elite' spelled as '1337'. It originated in early hacker and gaming communities in the 1980s-90s.
Most common replacements: A→4, E→3, I→1 or !, O→0, S→5, T→7, B→8, G→9, L→1. Advanced leet adds: Ph→f, ck→x, tion→shun, and combines symbols like |< for K, |_| for U, /-\ for A. The level of substitution varies by community and era.
Yes, this tool supports bidirectional conversion. Leet-to-English is less precise since some substitutions are ambiguous (1 could be I or L, 0 could be O), but the most common mappings are applied to produce the most likely English reading.
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