Decode resistor color bands or find the closest standard resistor value
This resistor calculator converts color bands to resistance values and finds the closest standard resistor value from the E12 or E24 series. Resistors use color-coded bands to indicate their resistance value, tolerance, and sometimes temperature coefficient.
The first two bands represent significant digits, the third band is the multiplier (power of 10), and the fourth band indicates tolerance. For example, a resistor with bands Yellow-Violet-Red-Gold is 47 × 100 = 4700 Ω with ±5% tolerance.
E12 and E24 are standard resistor value series defined by IEC. E12 has 12 values per decade (e.g., 1.0, 1.2, 1.5, 1.8, 2.2, 2.7, 3.3, 3.9, 4.7, 5.6, 6.8, 8.2) with ±10% tolerance. E24 has 24 values per decade with ±5% tolerance. This calculator helps you select the closest standard value.