Calculate electrical box fill per NEC Article 314.16. Includes conductors, equipment grounds, clamps, and device allowances.
Based on NEC 2023 Article 314.16
All calculations provided by SparkShift are for reference and estimation purposes only. Results must be verified by a licensed Professional Engineer (PE), licensed electrician, or qualified person before use in any installation, design, or permit application.
Using NEC 314.16 - volumes in cubic inches (in³)
Click a preset to auto-fill, or configure manually below
IMPORTANT LEGAL DISCLAIMER
For Reference Only: This calculator is provided for educational and informational purposes only. It is not intended to be a substitute for professional engineering design, advice, or certification.
Code Compliance: Calculations are based on the 2023 National Electrical Code (NEC®). However, local codes, amendments, and Authority Having Jurisdiction (AHJ) requirements vary by location and may supersede standard NEC requirements.
Verify with Your AHJ: Local Authority Having Jurisdiction (AHJ) requirements take precedence over all general code references. Contact your local building department or electrical inspector to confirm applicable codes, amendments, and permit requirements before beginning any electrical work.
No Liability: SparkShift, LLC and its affiliates assume no liability for errors, omissions, or the use/misuse of this tool. Users are solely responsible for verifying all results against applicable codes and standards before installation. Always consult a licensed electrician or Professional Engineer (PE).
NEC Reference: NEC 2023 Article 314.16
© 2026 SparkShift, LLC. Calculations are for reference only.
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