He looks like a mix, his coloring is somewhat yorkie but his face / muzzle looks like a mix. If you bought him from a BYB there is a good possibility he can be a mix.
A picture is just that, a picture.
Your vet can do DNA testing by a blood sample.
There is also a DNA kit you can buy, I don't know if that's the same price.
He is a little cutie for sure.
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