Resistor Color Code Calculator

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Decode 4, 5 and 6-band resistors. Pick the band colors and instantly read the resistance, tolerance and temperature coefficient with a live resistor preview.

Resistance –
Minimum value –
Maximum value –
Temperature coefficient –
Digit bands give the significant figures, the multiplier scales them, and the tolerance band sets the allowed range. The 6th band (when present) gives the temperature coefficient in ppm/°C.

About Resistor Color Code Calculator

This resistor color code calculator decodes 4-band, 5-band and 6-band resistors. Pick the color of each band and the resistance appears instantly, together with the tolerance, the minimum and maximum values that tolerance allows, and — for 6-band parts — the temperature coefficient. A live resistor preview redraws as you choose colors.

The bands follow the standard scheme: the first two (or three, on 5- and 6-band resistors) give the significant digits, the next band is the multiplier that scales them by a power of ten, and the following band sets the tolerance. The sixth band, when present, states the temperature coefficient in ppm/°C.

It is a free bench-side reference for anyone reading through-hole resistors — faster than a multimeter for sorting parts and safer than guessing whether that band is red or orange under workshop lighting.

How to use Resistor Color Code Calculator

  1. Select the band count: 4-band, 5-band or 6-band.
  2. Pick the color of each digit band.
  3. Set the multiplier band and the tolerance band — plus the temperature coefficient band on 6-band parts.
  4. Read the resistance, the min/max range and the tolerance from the live preview.

Frequently asked questions

The first two bands are significant digits, the third is the multiplier and the fourth is the tolerance. Red-violet-orange-gold decodes as 27 × 1,000 = 27 kΩ at ±5%.

A 5-band resistor adds a third significant digit before the multiplier, allowing more precise values — typical of ±1% precision parts. The reading order is otherwise the same.

It gives the temperature coefficient in ppm/°C — how much the resistance drifts per degree of temperature change. A brown sixth band, for example, indicates 100 ppm/°C.

Start from the band group nearest one end; the tolerance band (often gold or silver) sits alone at the other end with a wider gap. If a reading gives a non-standard value, try the reverse direction.

They are the nominal resistance plus and minus the tolerance. A 1 kΩ resistor at ±5% may legitimately measure anywhere between 950 Ω and 1,050 Ω — that spread is normal, not a fault.
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