Nouns ending in -aille are usually feminine, but le braille is masculine.
Braille is one of the rare exceptions: learn it as it is.
Is braille masculine or feminine?
lebrailleexception
The rule behind it
95.8% of -aille nouns are feminine
In context
Sais-tu écrire en Braille ?
Can you write Braille?
Qu'est-ce que Louis Braille a inventé ?