how many watts is the original charger for fhe ipad pro 12.9 inch

It depends on the exact iPad Pro 12.9" generation. See this support page:--> Identify your iPad model - Apple Support

When done, the answer to your question is in the support article that led you here.

• 1st & 2nd generation iPad Pro 12.9" = 12W
• 3rd & 4th generation iPad Pro 12.9" = 18W
• 5th generation iPad Pro 12.9" = 20W

Regards

Giulio

Following device need 12W power adapter

• iPad Pro 12.9-inch (2nd generation)
• iPad Pro 12.9-inch (1st generation)

Regards,

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