Leetspeak Converter

Leetspeak (written 1337 or l33t) is an internet-culture writing style that replaces letters with visually similar numbers and symbols. This converter encodes plain text into leet and decodes leet back to readable text, with a choice of a light readable style or a denser symbol-heavy one. It is used for gamertags, usernames, forum flair and nostalgia.

How it works

Encoding walks through your text one character at a time and swaps each letter for its leet equivalent, leaving anything without a mapping unchanged.

• Basic swaps six letters: a→4, e→3, i→1, o→0, t→7, s→5.
• Advanced swaps more and uses symbols: a→4, b→8, e→3, g→9, i→!, l→1, o→0, s→$, t→7, z→2.

Decoding reverses the swap with a single best-effort map. Because several letters can share a glyph (for example 1 may have come from i or l), decoding picks the most common source letter, so a decoded string may not perfectly match the original input.

Example

Encoding “Gera Tools are elite”:

In basic mode l and g are left as-is, so “Tools” becomes “700l5”; advanced mode also swaps l→1 and g→9. Decoding works the other way: “94m3r” returns “gamer” (9→g, 4→a, m→m, 3→e, r→r). Because some glyphs are ambiguous (1 decodes to i, not l), a round-trip is not always exact.

When to use basic vs advanced

Choose basic when readability matters — for a public gamertag or username that others need to recognise at a glance, basic leet keeps the text pronounceable. h4ck3r is immediately readable; h4ck3r in advanced becomes h4ck3r (same in this case, but strings with s, b, g, l, and i diverge visibly).

Choose advanced when you want the denser, more stylised look: for memes, retro hacker aesthetics, or creative writing involving fictional terminal output.

Decoding limitations

Leet has no single standard, so decoding is inherently approximate. The ambiguities that arise most often:

• 1 could be i or l — decoder returns i (more common)
• ! could be i or an actual exclamation mark — decoder returns i
• $ could be s or a dollar sign — decoder returns s
• 9 could be g or the digit nine — decoder returns g

If you are decoding leet written by someone else, the decoded result will usually be close but may differ in any of these letters. Treat it as a best-effort transliteration.

The conversion runs entirely in your browser and nothing is sent or stored.