Resistor colour code calculator for 4, 5 and 6-band resistors: colours to ohms and tolerance, or a value to its bands, snapped to E12, E24 or E96.
By AdminDrafted with AI writing toolsUpdated Checked examples: 9
Bands yellow, violet, red, gold mark 4.7 kΩ ±5%: any part between 4.465 kΩ and 4.935 kΩ is in spec. The value is in the E6 series.
Bands: yellow, violet → 47; red → ×10^2.
The resistor colour code in IEC 60062 marks a value with coloured bands: two or three significant digits, a multiplier band that gives the power of ten, a tolerance band, and on 6-band parts a temperature-coefficient band. It works both ways here: pick the colours to get the resistance and its tolerance range, or type a resistance to get the bands.
The default, yellow violet red gold, reads 47 × 10² Ω = 4.7 kΩ ±5%, so a part measuring anywhere from 4,465 Ω to 4,935 Ω is in specification. Going from a value to colours, the value can first be snapped to the nearest IEC 60063 preferred value: 5 kΩ is not in E12, so it becomes 4.7 kΩ, yellow violet red.
Gold and silver never start a reading because they carry no digit. When bands are faded or look alike, confirm the value with a multimeter.
Turn the resistor so the gold or silver band is on the right, then read from the left. On a four-band resistor the first two bands are digits, the third is a power-of-ten multiplier and the fourth is the tolerance. Red (2), red (2), brown (×10), gold (±5%) reads 22 × 10 = 220 Ω ±5%.
Five-band resistors carry a third digit before the multiplier, and six-band resistors add a temperature-coefficient band at the end. The code is set by IEC 60062:2016 (IEC publication page).
Each color stands for the same number as a digit and as a multiplier exponent: red is the digit 2 and the multiplier 10² = 100. Vishay's color code chart gives the same pattern with worked four- and five-band examples.
| Color | Digit | Multiplier |
|---|---|---|
| Black | 0 | 1 |
| Brown | 1 | 10 |
| Red | 2 | 100 |
| Orange | 3 | 1000 |
| Yellow | 4 | 10000 |
| Green | 5 | 100000 |
| Blue | 6 | 1000000 |
| Violet | 7 | 10000000 |
| Grey | 8 | 100000000 |
| White | 9 | 1000000000 |
Three colors never appear as digits:
The band's position decides which meaning applies. Gold as the third of four bands is a ×0.1 multiplier; as the fourth, it is ±5%.
Join the digit bands into one number, then apply the multiplier. Green, blue, gold, gold is 56 × 0.1 = 5.6 Ω ±5%; brown, black, black, brown, brown is 100 × 10 = 1,000 Ω ±1%.
| Bands | Resistance (ohms) | Tolerance (%) | Minimum (ohms) | Maximum (ohms) |
|---|---|---|---|---|
| yellow, violet, red, gold | 4700 | 5 | 4465 | 4935 |
| green, blue, gold, gold | 5.6 | 5 | 5.32 | 5.88 |
| brown, black, black, brown, brown | 1000 | 1 | 990 | 1010 |
| orange, orange, black, brown, brown, red | 3300 | 1 | 3267 | 3333 |
| brown, black, orange | 10000 | 20 | 8000 | 12000 |
In the six-band row, orange, orange, black, brown gives 330 × 10 = 3,300 Ω, the next brown band means ±1%, and the final red band means 50 ppm/K. The three-band part has no tolerance band, so brown, black, orange is 10 kΩ ±20%.
A resistor marked R with tolerance t% can measure anywhere from R × (1 − t/100) to R × (1 + t/100). Yellow, violet, red, gold is 4.7 kΩ ±5%, so any reading from 4,465 Ω to 4,935 Ω is in specification.
A coefficient of α ppm/K changes the resistance by about ΔR ≈ R × α × 10⁻⁶ × ΔT. The 3,300 Ω, 50 ppm/K resistor in the table drifts 0.165 Ω per kelvin, or about 4.1 Ω over a 25 K rise.
Write the value with two significant digits for four bands, or three for five and six bands, then count the power of ten. 4.7 kΩ is 47 × 10² Ω, so its bands are yellow, violet, red. 0.22 Ω is 22 × 10⁻² Ω and needs a silver multiplier: red, red, silver.
Values with more digits are rounded to fit. 1,234 Ω is marked 1,200 Ω (brown, red, red) on four bands and 1,230 Ω (brown, red, orange, brown) on five.
Resistors are sold in preferred values from the IEC 60063 E-series. E12 has no 5 kΩ part; the nearest is 4.7 kΩ, because 5,000 ÷ 4,700 ≈ 1.064 is a smaller step than 5,600 ÷ 5,000 = 1.12.
To size a resistor for a voltage and current, use the Ohm's law calculator. For several resistors in a circuit, use the series and parallel calculator or the voltage divider and LED resistor calculator.
Checked against: IEC 60062 table: 4,7 × 10² Ω, gold = ±5%; 4700 × 0.95 / 1.05
Checked against: IEC 60062 table: 100 × 10¹ Ω ±1%
Checked against: IEC 60063 E12 neighbours 4.7k and 5.6k: 5000/4700 = 1.064 < 5600/5000 = 1.12
Checked against: IEC 60062 table: 330 × 10 Ω, brown ±1%, red TCR 50 ppm/K
The first two bands are digits, the third is the multiplier and the fourth the tolerance. The digits run black 0, brown 1, red 2, orange 3, yellow 4, green 5, blue 6, violet 7, grey 8, white 9. Yellow, violet, red, gold therefore reads 47 × 10² = 4,700 Ω, with gold meaning ±5%.
Start from the end away from the gold or silver band. Gold and silver have no digit value in IEC 60062; they only appear as a multiplier (×0.1 and ×0.01) or a tolerance (±5% and ±10%). The first band usually sits closer to its lead, and the tolerance band is often spaced apart from the others.
A 4-band resistor carries two significant digits, enough for the E6 to E24 values used for ±5% to ±20% parts. A 5-band resistor carries three digits for the E48 to E192 values of ±2% and tighter parts: brown, black, black, red, brown is 100 × 10² Ω = 10 kΩ ±1%. A 6-band resistor adds a temperature-coefficient band.
It gives the resistance drift per kelvin in parts per million: brown 100 ppm/K, red 50, yellow 25, green 20, orange 15, blue 10, violet 5 and grey 1. A 3.3 kΩ resistor with a red band changes by 3,300 × 50 × 10⁻⁶ = 0.165 Ω per degree, about 4.1 Ω over a 25 °C rise.
A missing tolerance band means ±20%. Brown, black, orange with no fourth band is 10 kΩ, and any value from 8 kΩ to 12 kΩ is within specification. Such parts come from the E6 series (1.0, 1.5, 2.2, 3.3, 4.7, 6.8), whose steps of about 47% suit the wide tolerance.
This calculator includes 9 worked examples with independently sourced answers. They run in the test suite, and you can run them here too.