How to use it
- Choose the Number of bands on the drawn resistor: 4, 5 or 6.
- Choose the colour of each band in its list. The drawing follows, and the value, tolerance and range appear under it.
- To find the bands for a value, type it in Value (for example 4k7), and choose the Number of bands and the Tolerance band you need.
- The drawing and the reading then show the bands for that value. Check the note: when the bands cannot give the value exactly, the nearest value is shown.
The colour code
The colour code of resistors is set by IEC 60062:2016. The first bands are the digits, the next the multiplier, then the tolerance, and on six-band resistors a temperature coefficient (TCR). The values below are those of the standard as listed on Wikipedia.
- On a 4-band resistor the first two bands are digits, the third is the multiplier and the fourth the tolerance.
- On 5 and 6-band resistors there are three digits; the sixth band of a 6-band resistor is the temperature coefficient.
- A resistor with no fourth band has a tolerance of ±20 %.
| Colour | Digit | Multiplier | Tolerance | TCR (ppm/K) |
|---|---|---|---|---|
| Black | 0 | ×10⁰ | – | 250 |
| Brown | 1 | ×10¹ | ±1 % | 100 |
| Red | 2 | ×10² | ±2 % | 50 |
| Orange | 3 | ×10³ | ±0.05 % | 15 |
| Yellow | 4 | ×10⁴ | ±0.02 % | 25 |
| Green | 5 | ×10⁵ | ±0.5 % | 20 |
| Blue | 6 | ×10⁶ | ±0.25 % | 10 |
| Violet | 7 | ×10⁷ | ±0.1 % | 5 |
| Grey | 8 | ×10⁸ | ±0.01 % | 1 |
| White | 9 | ×10⁹ | – | – |
| Gold | – | ×10⁻¹ | ±5 % | – |
| Silver | – | ×10⁻² | ±10 % | – |
| No band | – | – | ±20 % | – |
E24 and E96 values
Resistors are made in preferred values: the E24 series has 24 values in each decade (4.7 kΩ and 5.1 kΩ among them), and E96 has 96. IEC 60063 defines them, as listed on Wikipedia. The page names the nearest value of each series for the value you type, because a band code can only give the preferred values.
What this page does not cover
- The fifth band of military resistors, which some parts use to show the failure rate.
- The three- and four-digit codes printed on small surface-mount resistors, which follow a different system.
- Resistors whose colours are not to IEC 60062: check the datasheet of very old or special parts.
Worked example: yellow violet red gold
The digits are 4 and 7, the multiplier red is 10², and the tolerance gold is ±5 %. The value is 47 × 10² Ω = 4.7 kΩ.
The range is 4.7 kΩ × 0.95 = 4.465 kΩ to 4.7 kΩ × 1.05 = 4.935 kΩ.
Going the other way, 4.75 kΩ with four bands cannot be made exactly: the nearest it gives is 4.8 kΩ (48 × 10² Ω). With five bands it is exact: yellow violet green brown (475 × 10¹ Ω).
Frequently asked questions
Which band is the tolerance band?
On a four or five-band resistor it is the last band: gold is ±5 %, silver ±10 %, and no band means ±20 %. On a six-band resistor it is the fifth band, and the sixth is the temperature coefficient.
What do the gold and silver multipliers mean?
Gold is a multiplier of 0.1 and silver of 0.01. Yellow violet red gold is 4.7 kΩ, while brown black gold gold is 1 Ω.
What is the temperature coefficient band?
On a six-band resistor it gives how much the resistance changes per degree Celsius, in parts per million: brown is 100 ppm/K and red 50 ppm/K. Smaller numbers mean a more stable resistor.
Why does the page give a nearest value?
The bands can only make a value with two or three significant figures and a multiplier, so some values cannot be made exactly. The nearest value the bands make is shown with a note.
How do I read a resistor when the colours are hard to see?
Start from the end with the gold or silver band, which is the tolerance band, and read the bands towards it. Some colours look alike, such as brown and red, so a meter reading settles the value.
Sources
- Wikipedia: Electronic color code (IEC 60062:2016 bands, tolerances and TCR)
- Wikipedia: E series of preferred numbers (E24 and E96, IEC 60063)
Figures and text last checked on Tuesday, November 10, 2026.