Free PCB design calculators
13 calculators for the numbers that decide whether a first prototype works: copper, impedance, power stages and passives. Each one explains the formula, its limits and the mistakes we see most in design reviews.
Layout & fabrication
Trace widthMinimum width for a current, copper weight and temperature rise.
Trace resistance & voltage dropResistance, IR drop and power loss of a copper trace.
Via current & resistanceCurrent capacity, resistance and thermal resistance of a via.
Impedance (microstrip & stripline)Single-ended and differential impedance, microstrip and stripline.
Power
MLCC DC biasEffective capacitance of ceramic capacitors at working voltage.
LDO / linear regulator thermalPower dissipation, junction temperature and safe current.
Buck / boost converterInductor, peak current, output capacitance and ripple.
Circuit design
Voltage divider (E24/E96)Best E24/E96 resistor pair, error and worst-case output.
LED series resistorSeries resistor, nearest standard value and power.
I²C pull-up resistorValid pull-up range from bus speed and capacitance.
Crystal load capacitorsC1/C2 values from crystal load capacitance and stray.
RC low-pass filterCutoff, time constant, settling and attenuation.
System