Box Fill Calculator
Calculate electrical box fill to prevent overcrowding
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How to Use This Calculator
Box size.
Wire count.
Devices.
Pass/Fail.
Understanding Box Fill Calculations
Crowding heat.
Short circuits.
Volume allowance.
Extensions.
Formula & Calculations
Sum(Wire Vols) + Sum(Device Vols)
Key Factors to Consider
Wire gauge
Clamps
Grounds
Mud rings
Frequently Asked Questions
1Standard box?
18-22 cu in.