Precisely calculate the maximum current capacity of your PCB traces with our free online tool. Prevent overheating and ensure reliable circuit board performance by factoring in trace width, copper thickness, layer type, and temperature rise using IPC-2221 guidelines. Ideal for engineers and hobbyists designing printed circuit boards.
Formula:
The calculator uses an empirical formula based on IPC-2221 Section A-7 guidelines for determining trace current capacity:
I = k × (ฮT_C)b × (Area_mils)c
- I: Maximum Current in Amperes (A)
- k: Constant (0.048 for external layers, 0.024 for internal layers)
- ฮT_C: Desired Temperature Rise in degrees Celsius (°C)
- Area_mils: Trace cross-sectional area in square mils. Calculated as Width_mils × Thickness_mils
- Width_mils: Trace width in mils
- Thickness_mils: Copper thickness in mils (1 oz copper = 1.378 mils)
- b: Exponent, typically 0.44
- c: Exponent, typically 0.725