no-nepali-profanity

A small, dependency-free profanity matcher for English, Romanized (Latin) Nepali and Devanagari Nepali, plus the Hindi slang common in Nepal. Built for moderating user-written text — names, comments, reviews — on Nepali sites, where false positives on real names are more damaging than a missed swear.

Zero runtime dependencies. Python ≥ 3.9. A direct port of the no-nepali-profanity npm package, with the same word lists and matching rules.

Documentation: mukhxadnahunna.com/python

Install

pip install no-nepali-profanity

Usage

from no_nepali_profanity import contains_profanity, find_profanity, tokenize

# boolean check — fastest
contains_profanity("Great teacher!")        # False
contains_profanity("muji")                  # True
contains_profanity("मुजीको कक्षा")           # True  (Devanagari + postposition)

# which words — returns normalised matches as they appeared
find_profanity("f.u.c.k this sh1t")        # ["fuck", "shit"]
find_profanity("f u c k this")              # ["fuck"]
find_profanity("Randip Thapa")              # []
find_profanity("*ss teacher")               # ["*ss"]

# debugging — see what the matcher actually splits into
tokenize("Great teacher!")                  # ["great", "teacher"]

API

Match positions (ProfanityMatch.start, end) are character (code point) indices, unlike the npm package which uses UTF-16 code units.

Censoring

censor("you muji")                                   # "you ****"
censor("F.U.C.K this Sh1t!")                          # "******* this ****!"
censor("you muji", {"mask": "#"})                     # "you ####"
censor("you muji", {"replace": lambda m: "[censored]"})  # "you [censored]"
find_profanity_matches("you muji")                     # [ProfanityMatch(text="muji", normalized="muji", start=4, end=8)]

Check and censor in one pass:

result = check("you muji")
result.has_profanity   # True
result.words           # ["muji"]
result.censor()        # "you ****"

Options

find_profanity("fuck muji मुजी", {"languages": ["romanized"]})      # ["muji"]
contains_profanity("you idiot", {"strictness": "lenient"})         # False
find_profanity("damn it", {"strictness": "strict"})   # ["damn"]

• languages: any of "english", "romanized", "devanagari". Default: all three.
• strictness: "lenient" (severe words only), "standard" (default, adds milder insults like idiot, murkha) or "strict" (adds entries that are also ordinary words, like damn, and the stems rand, cond, kand, lund; names they would hit, like Randip, are on a built-in allow list).
• extra_words: more words to flag. allow_words: words never to flag, such as names on your site.

What it catches

• Case and Unicode forms: IDIOT, full-width letters.
• Leetspeak: sh1t, @ss (0 1 3 4 5 7 @ $).
• ! for i between letters: sh!t, b!tch. Sentence-final Great teacher! is left alone.
• * for a hidden letter: f*ck, sh*t, and markdown emphasis like *sh*t* still reads as the word.
• Stretched letters: fuuuuck, for words of 4+ letters.
• Spelled-out letters: f.u.c.k, f u c k.
• Nepali postpositions and plurals glued on: mujiko, randiharu, मुजीको, …हरू.
• Devanagari spelling variants: nukta, chandrabindu vs anusvara, zero-width joiners.
• Stems where no ordinary word starts the same way: fucking, bitches, machiknee.
• Multi-word phrases: chaak ko pwal, pesa garne, sasto manche (Latin and Devanagari).

What it deliberately doesn't

• Short words match exactly, so as, class, assignment and Assam are fine.
• Name collisions: shit is a whole word only, because Shitij / शितिज is a name. Names like मुजी-adjacent Randip / राण्डीप, Putali / पुतली, Asha / आशा are checked in the test suite.
• No caste names, surnames or ordinary words that are only offensive in context (e.g. kami, kukur). A word list can't tell a slur from someone's name; that needs human moderation.
• No judgement of context, sarcasm or meaning. This is a first-pass filter, not a moderator.

Development

python -m venv .venv && .venv/bin/pip install -e ".[test]"
.venv/bin/pytest

The word lists live in src/no_nepali_profanity/lexicon.py, apart from the matching logic in src/no_nepali_profanity/core.py. Native-speaker review of the Nepali lists is the most valuable contribution.

License

MIT