MOSFET gate resistor calculator

The trade this tool cannot make for you: a small gate resistor switches fast, which keeps switching loss down, but it also dumps more current into the gate loop and invites ringing and EMI; a large one is quiet and slow. Watch the peak currents against what your driver can actually source and sink. The model is first order on purpose: no input capacitance, no internal gate resistance, no reverse recovery of the freewheeling diode, no parasitic inductance in the gate loop, and the switching-loss rectangle assumes hard switching with a clamped inductive load. Datasheet Qg figures are quoted at a specific Vgs and Vds; if your drive differs, the real charge does too.