Box Fill Volume - 6x8 - 8x8

[mobiledynamics]

Looking at pull box. Ideally, 6x8 would the preferred splice box I use. Otherwise it's a 8x8. Both 4" Deep

For Sixteen to twenty 12AWG wires, and four 10AWG wires, am I OK on the volume fill with the 6x8 box

 

[PRH44]

6 X 6 X 4 is more than fine according to NEC Calc. #12=2.25 square inches. #10=2.50 square inches.
8 X 8 would be more comfortable

 

[Blk88GT]

I used a bunch of 8x8s in my shop and have no regrets.

 

[Highbeam]

Bigger is better. It starts getting crowded in there after awhile. You'll need a way to hold everything in when you put the lid on.