Fundamentals
Ohm's Law
Voltage, current & resistance
Current Divider
Parallel resistor current
Power Calculator
Power, voltage, current
Voltage Divider
Resistor divider circuits
Pull-up / Pull-down
Digital logic resistors
RC Time Constant
RC charging/discharging
Star-Delta Conversion
3-phase networks
Components & Wire
Resistor Color Code
Decode band colors
SMD Resistor Code
Surface-mount markings
Capacitor Code
Find capacitance values
LED Series Resistor
Current-limiting resistor
AWG Wire Gauge
American standard
SWG Wire Gauge
British/Indian standard
Power & Solar
Inverter Matching
Right inverter & battery
Battery Backup Time
How long will it last
Battery Charging Time
Estimate charge time
Solar Calculator
Panel & battery sizing
AC Load Calculator
Home power & cost
DC Load Calculator
Off-grid DC loads
Energy Calculator
Wh and kWh consumption
AC & Signals
AC Power Calculator
Single/3-phase power
Power Triangle
Real, Reactive, Apparent
RMS Voltage
RMS, Peak & Average
LC Resonant Freq
LC tank circuit
Decibel (dB)
Power & voltage gain
Freq & Wavelength
Hz and meters
Duty Cycle
PWM signal parameters
Rise Time & BW
tr = 0.35 / BW rule
Period / Frequency
Convert T & f
Calculate Active (Real), Apparent, and Reactive power for single-phase and three-phase AC systems.