Fundamentals
Ohm's Law
Voltage, current & resistance
Inverter Calculator
Power & battery sizing
Voltage Divider
Resistor divider circuits
Pull-up / Pull-down
Digital logic resistors
Components
Resistor Color Code
Decode band colors
SMD Resistor Code
Surface-mount markings
Capacitor Code
Find capacitance values
LED Series Resistor
Current-limiting resistor
Wire & Networks
AWG Wire Gauge
American standard
SWG Wire Gauge
British/Indian standard
Star-Delta Conversion
3-phase networks
Power & Battery
Battery Backup Time
How long will it last
Battery Charging Time
Estimate charge time
Inverter Matching
Right inverter & battery
AC Load Calculator
Home power & cost
DC Load Calculator
Off-grid DC loads
Solar Calculator
Panel & battery sizing
Size your solar panel array, battery bank, charge controller, and inverter based on your daily load and sun hours.
Enter your load and location details
Use the AC Load Calculator to find this value