What letters get substituted?

a→4, e→3, i→1, o→0, s→5, t→7, l→1, b→8. Configurable — toggle off specific substitutions if you want partial leet.

Is this strong obfuscation?

No — it's a cosmetic transform. Search engines, moderation filters, and spam detection all unleet before processing. Don't use for real security.

Yes — toggle direction. Decoding assumes standard substitutions; unusual leet (using @ for a, $ for s) needs the 'custom substitutions' option.

Leet is lowercase-biased traditionally. Toggle 'preserve case' to keep your original capitalization on non-substituted letters.

Convert text to/from 1337 speak. Part of the DevTools Surf developer suite. Browse more tools in the Fun / Niche collection.

Leet speak (1337) originated in 1980s BBS culture as a way to bypass text filters and mark elite status among hackers.
The word 'leet' itself derives from 'elite,' and early BBS sysops granted '31337' access levels to trusted users.
Google has a full leet speak interface: searching from 'Google 1337' (google.com/intl/xx-hacker/) translates the entire UI into leet.

What letters get substituted?: a→4, e→3, i→1, o→0, s→5, t→7, l→1, b→8. Configurable — toggle off specific substitutions if you want partial leet.
Is this strong obfuscation?: No — it's a cosmetic transform. Search engines, moderation filters, and spam detection all unleet before processing. Don't use for real security.
Can I decode leet?: Yes — toggle direction. Decoding assumes standard substitutions; unusual leet (using @ for a, $ for s) needs the 'custom substitutions' option.
Does it preserve case?: Leet is lowercase-biased traditionally. Toggle 'preserve case' to keep your original capitalization on non-substituted letters.

Convert text to/from 1337 speak. Part of the DevTools Surf developer suite. Browse more tools in the Fun / Niche collection.

Leet speak (1337) originated in 1980s BBS culture as a way to bypass text filters and mark elite status among hackers.
The word 'leet' itself derives from 'elite,' and early BBS sysops granted '31337' access levels to trusted users.
Google has a full leet speak interface: searching from 'Google 1337' (google.com/intl/xx-hacker/) translates the entire UI into leet.

What letters get substituted?: a→4, e→3, i→1, o→0, s→5, t→7, l→1, b→8. Configurable — toggle off specific substitutions if you want partial leet.
Is this strong obfuscation?: No — it's a cosmetic transform. Search engines, moderation filters, and spam detection all unleet before processing. Don't use for real security.
Can I decode leet?: Yes — toggle direction. Decoding assumes standard substitutions; unusual leet (using @ for a, $ for s) needs the 'custom substitutions' option.
Does it preserve case?: Leet is lowercase-biased traditionally. Toggle 'preserve case' to keep your original capitalization on non-substituted letters.