Resistor Color Code Calculator

Pick the band colors and read the resistance, tolerance and temperature coefficient — for 4, 5 and 6-band resistors, with a live diagram that updates as you choose. Runs in your browser.

Resistance
Tolerance
Value range

How to read a resistor color code

Resistors use colored bands to mark their value. Read from the end where the bands are grouped closest to the edge:

The tolerance band is often gold or silver and slightly separated from the rest — that's your clue for which way round to read it.

Color code chart

ColorDigitMultiplierTolerance
Black0×1
Brown1×10±1%
Red2×100±2%
Orange3×1k
Yellow4×10k
Green5×100k±0.5%
Blue6×1M±0.25%
Violet7×10M±0.1%
Grey8×100M±0.05%
White9×1G
Gold×0.1±5%
Silver×0.01±10%

Worked example: 10 kΩ

Brown (1), black (0), orange (×1,000) → 10 × 1,000 = 10,000 Ω = 10 kΩ. Add a gold band for ±5% tolerance, meaning the real value sits between 9.5 kΩ and 10.5 kΩ.

Private by design. Everything is computed in your browser — nothing is uploaded. This site is static.

Frequently asked questions

How do you read resistor color codes?

From the grouped end: first bands are digits, then the multiplier (zeros), then tolerance. 5/6-band add a third digit and a temp-coefficient band.

What color is a 10k resistor?

4-band: brown, black, orange, + tolerance (often gold). 1-0 = 10, ×1,000 = 10 kΩ.

Which end do I start from?

The side with bands closest to the edge; the tolerance band (often gold/silver, slightly separated) is last.

What does tolerance mean?

How far the real value can stray: gold ±5%, silver ±10%, brown ±1%, red ±2%.

More free tools

Other calculators: Aspect Ratio Calculator, Grams to Cups · See all Alienated Tools.