This list was generated indiscriminately from Wiktionary's database. As a result, it contains heavy profanity, rarely-used or outdated plural forms, words and phrases that are debatably nouns, and inaccuracies.
Also, it's not sorted. Sorry.
word1
countability (1 = has a plural, 2 = sometimes has a plural, 3 = no plural or unknown)
plural forms (separated by commas if there are multiple)
word2
...
Example:
violin
1
violins
pinyin
3
electric
2
electrics
octopus
1
octopuses,octopi,octopodes,octopii