Leetspeak generator and translator — write 1337 and read it back

How to use the leetspeak generator

1. Type or paste into Your text (the sample is “Elite hackers write leet speak”).
2. Choose a Direction: Text → leet to convert, or Leet → text to translate back.
3. Choose a Substitution: Light (4 3 1 0 5 7) or Heavy (every letter).
4. Press Copy under the result.

What it does and when to use it

Leetspeak (from “elite”) began in 1980s bulletin-board and hacker culture, where swapping letters for digits made words look insider-only. Today it shows up in gamer tags, retro-hacker jokes, puzzle hunts and playful captions. Light leet keeps a word recognisable (h4ck3r); Heavy leet makes a small cipher that friends must decode.

Because leet is plain ASCII, it displays on every device, unlike Unicode fancy styles. For other text codes, try ROT13, Morse code or the A1Z26 cipher. To see the Light leet style beside 30-plus others, open fancy text in all styles.

How it works

Encoding looks at each character, lower-cases it for the lookup and swaps it if the chosen table has an entry. Upper and lower case give the same symbol. Light uses a→4, e→3, i→1, o→0, s→5, t→7. Heavy uses this table:

a 4    b 8    c (    d |)   e 3    f |=   g 6    h #    i !
j _|   k |<   l 1    m |\/| n |\|  o 0    p |*   q 0_   r |2
s 5    t 7    u |_|  v \/   w \/\/ x ><   y `/   z 2

Decoding reverses the table. It scans from left to right and always tries the longest symbol group first, so |\/| is read as m before \/ could be read as v, and |2 as r before 2 could be read as z. Anything that matches no symbol is kept as it is.

Worked examples

From the tool’s own function:

• Noob gamer, Light → N00b g4m3r. N, b, g, m and r have no Light symbol and stay.
• Noob gamer, Heavy → |\|008 64|\/|3|2. Every letter is replaced.
• 1 l0v3 7h15, Leet → text, Light → i love this.
• #31|*, Leet → text, Heavy → help.
• A warning case: 70p 10 5173 decoded with Light gives top io site; the real number 10 was read as letters.

Limits and tips

• Hard for screen readers and search. A screen reader reads N00b as “N zero zero b” and Heavy leet as a long list of symbol names. Search will not match leet to the real word. Keep anything people must read or find in plain text.
• Decoding is a best guess, not an exact reverse, because symbols such as 1 and 0 are shared with real numbers.
• Conversion runs in your browser; nothing is uploaded.