Leet Speak Translator
Convert plain text to leet speak (1337) and translate leet back to readable text with the classic digit-and-symbol substitutions.
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What this tool does
Convert plain text to leet speak (1337) and translate leet back to readable text with the classic digit-and-symbol substitutions. This is basic leet (the widely shared substitution set), not advanced multi-character leet (|-| for H, |/\/| for M), which cannot be decoded unambiguously. Both i and l encode to 1, so decoding reads 1 as i — a known, unavoidable ambiguity of classic leet.
How to use the Leet Speak Translator
- Enter or select text.
- Enter or select direction.
- Read the calculated result; change any measurement to compare alternatives.
Formula
Encoding substitutes each replaceable letter with its classic leet glyph (a → 4, e → 3, i/l → 1, o → 0, s → 5, t → 7 and so on); letters without a classic glyph pass through. Decoding reverses the table, mapping 1 back to i (the i/l ambiguity is noted below).
- text
- Text
- mode
- Direction
This is basic leet (the widely shared substitution set), not advanced multi-character leet (|-| for H, |/\/| for M), which cannot be decoded unambiguously. Both i and l encode to 1, so decoding reads 1 as i — a known, unavoidable ambiguity of classic leet.
Worked example
For leet speak translator, the following measurements illustrate the exact method: Text: Leet speak; Direction: encode.
Inputs
- TextLeet speak
- DirectionText → Leet speak
Result
- Result1337 5p34k
Results explained
- Result
- Result from the formula above. This is basic leet (the widely shared substitution set), not advanced multi-character leet (|-| for H, |/\/| for M), which cannot be decoded unambiguously. Both i and l encode to 1, so decoding reads 1 as i — a known, unavoidable ambiguity of classic leet.
Frequently asked questions
Leet (1337, from 'elite') is an informal writing system from early bulletin-board and gaming culture that replaces letters with similar-looking digits and symbols: the word leet itself becomes 1337 — e becomes 3, a becomes 4, s becomes 5 and t becomes 7.
Classic leet uses 1 for both i and l, so the encoding loses the distinction and no decoder can recover it with certainty. This translator decodes 1 as i; if a decoded word looks wrong, the 1 may have been an l.
Basic leet uses one character per letter (the set used here) and stays decodable. Advanced leet builds letters from multiple characters — H as |-|, M as /\/\ — which looks striking but is ambiguous and often unreadable to decoders.
Mostly playfully: gamer tags, display names, puzzle hunts and retro internet humour, and (seriously) as a source of password variations — which is exactly why leet substitutions of dictionary words are weak passwords.
Yes. Translation is a substitution table in your browser; nothing you type is uploaded or stored.