Which generation of Apple pencil can I use for my ipad 5th generation

iPad5 does not support Apple Pencil.

Here is the full compatibility list:

Apple Pencil (2nd generation)

You can use Apple Pencil (2nd generation) with these iPad models: 

• iPad Pro 12.9-inch (3rd generation) and later
• iPad Pro 11-inch (1st generation) and later
• iPad Air (4th generation)

Apple Pencil (1st generation)

You can use Apple Pencil (1st generation) with these iPad models:

• iPad (8th generation)
• iPad mini (5th generation)
• iPad (7th generation)
• iPad (6th generation)
• iPad Air (3rd generation)
• iPad Pro 12.9-inch (1st or 2nd generation)
• iPad Pro 10.5-inch
• iPad Pro 9.7-inch

Not sure which iPad you have? Identify your iPad model.

https://www.apple.com/apple-pencil/

no apple pen work with that model,

you can use a normal capacitive stylus though

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