Transform plain text to 1337 speak

Render a fixed ten-letter form of 1337 by replacing lookalike Latin letters with single digits.

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ToolLeet Speak
Input
Output
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Preview

How it works

A one-character table changes a, b, e, g, i, l, o, s, t, and z to 4, 8, 3, 9, 1, 1, 0, 5, 7, and 2 in either case. All other code points stay where they are; there is no reverse pass because i and l collide at 1 and leetspeak has no standard substitution alphabet.

  • The spelling 1337 represents elite through the familiar e→3, l→1, and t→7 substitutions.
  • Only single digits are emitted, excluding multi-character variants such as |) for d.

Worked example

Transform plain text to 1337 speak
Convert 'Hello World' showing common letter substitutions
Input
											Hello World
Output
												H3110 W0r1d

When to use this

Bulletin-board history uses 1337 as online slang, retro game profiles imitate early hacker typography, and moderation test corpora exercise substitutions that exact-word filters can miss.

Edge cases

  • I and l both become 1, making an output such as 111 impossible to decode uniquely.
  • Uppercase and lowercase variants collapse to the same digit, so substituted positions lose their original case.
  • Accented letters, @ for a, and multi-symbol forms remain unchanged because they are outside the ten-entry mapping.