Type your text and choose light or heavy substitution, and the tool converts it to leetspeak (l33t) by swapping letters for lookalike numbers and symbols.
Leetspeak (or 'l33t sp34k') is an internet slang that replaces letters with numbers and symbols that resemble them, like A→4, E→3, and O→0. It started in online gaming and hacker communities.
Light mode swaps common vowels and a few letters (a→4, e→3, i→1, o→0, s→5, t→7). Heavy mode adds more aggressive substitutions like b→8, g→9, l→|, and z→2 for a more extreme look.
Light mode decodes cleanly. Heavy mode can be ambiguous or lossy — for example '|' could map back to L or I — so decoding is best-effort and may not perfectly restore the original text.