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
Decode 3-digit and 4-digit surface mount (SMD) resistor marking codes into resistance values.
Enter the code printed on the SMD resistor
Standard EIA-96 markings use 3 or 4 digits. The last digit is the multiplier (power of 10).
First 2 digits are significant; 3rd is the multiplier.
First 3 digits are significant; 4th is the multiplier.
If the code contains an "R", it acts as a decimal point. Example: 4R7 = 4.7Ω, R22 = 0.22Ω.