Wire Size Estimator & Reference
Estimate a minimum wire size based on load current, conductor type, and whether the load is continuous.
Use the estimator for a quick starting point, then compare copper and aluminum typical reference sizes below.
Tool status
Wire Size Estimator results are temporarily unavailable
Calculation results for this tool are temporarily unavailable while its engineering assumptions and electrical guidance are being reviewed. The educational information on this page remains available.
Electrical work should be evaluated for the specific installation and applicable local requirements.
Related problems and reference
Planning and safety note
This content is for general learning and planning. Always verify work against current NEC requirements, manufacturer instructions, and local code rules. If you are unsure or see heat, sparks, burning smell, repeated trips, or damaged wiring, contact a licensed electrician.
For accurate readings and safe testing, having the right tools matters.See recommended tools →