Use this browser-based tool for an initial engineering estimate. Inputs remain in this page and are not sent to a server.
Method and units
For a uniform rectangular copper trace, R = ρL/(wt). The width required by the entered voltage-drop limit is w = ρLI/(ΔVt), using ρ = 1.724 × 10⁻⁸ Ω·m at approximately 20 °C.
Model limits
This sizes for DC voltage drop, not allowable temperature rise or current capacity. Copper temperature, neck-downs, planes, thermal environment and the relevant current-carrying design method require separate review.
Use the result in your project
Record the assumptions with the result. Check actual material and component data, evaluate tolerances and confirm the proposed construction before releasing manufacturing files.