Per cracker? yikes.

Without knowing what program you follow, it's hard to give advice on this.

For someone on keto, probably not. If you are following low carb to control blood sugar, probably not. If you are someone who struggles to have something like this, and limit your quantities, probably not.

If your carb targets are higher, sure. If you aren't concerned about ketosis, go for it. If you don't binge when you've had just one, they should be fine.

Something like these would be better though:
http://www.kitchentablebakers.com/products_agedparmesan.php

Or try making them -
http://www.foodnetwork.com/recipes/ina-garten/parmesan-crisps-recipe/index.html