How do 4-band, 5-band, and 6-band resistors differ?

4-band resistors use 2 significant digits, multiplier, and tolerance. 5-band resistors use 3 significant digits for better precision. 6-band resistors add temperature coefficient (ppm/°C).

Why is the first band never black in the calculator?

The first significant digit cannot be zero in standard resistor color coding. Black represents 0 and is valid for later significant digits, but not the first one.

What does tolerance mean in resistor selection?

Tolerance indicates allowed variation from nominal value. A 10 kΩ resistor with ±5% tolerance can be between 9.5 kΩ and 10.5 kΩ.

When should I care about ppm/°C?

Temperature coefficient matters in precision, drift-sensitive, or high-temperature environments. Lower ppm/°C means resistance changes less with temperature.

Home / Tools / Resistor Color Code Calculator

Reference Utility

Resistor Color Code Calculator

Resistor Color Code Calculator supports engineering calculations with transparent assumptions, practical result interpretation, and links to next-step technical resources.

Legend & Visual Output

Decoded Value

Select band colors

Color Legend Quick Reference

Black

Digit 0

Brown

Digit 1

Red

Digit 2

Orange

Digit 3

Yellow

Digit 4

Green

Digit 5

Blue

Digit 6

Violet

Digit 7

Gray

Digit 8

White

Digit 9

Gold

Special

Silver

Special

Inputs & Outputs

1st Band

▼

2nd Band

▼

Multiplier

▼

Tolerance

▼

Calculated Result

Resistance

Tolerance

Resistance Range

Assumptions & Usage Notes

Use this decoder for intact, standard axial resistor markings. If the body paint is heat-damaged, the tolerance band is ambiguous, or the part may be non-standard, confirm with direct measurement before using the decoded value in design work.

The Resistor Color Code System

While 4-band resistors are common in general electronics, many industrial and precision designs use 5-band or 6-band types to improve numeric resolution and temperature stability.

Type	Bands	Meaning	Typical Use
4-band	Digit 1, Digit 2, Multiplier, Tolerance	Standard identification with two significant digits.	General control circuits, power rails, and utility boards.
5-band	Digit 1, Digit 2, Digit 3, Multiplier, Tolerance	Higher precision with three significant digits.	Industrial measurement loops and tighter analog design.
6-band	Digit 1, Digit 2, Digit 3, Multiplier, Tolerance, Tempco	Adds temperature coefficient (ppm/°C) for drift control.	Precision instrumentation and thermal-sensitive systems.

Standard Color Mapping Reference

Use this quick reference when manually decoding resistor bands. Your calculator selections follow the same mapping for digit, multiplier, tolerance, and temperature coefficient.

Color	Digit	Multiplier	Tolerance	Tempco	Engineering Note
Black	0	×10^0	—	—	Base digit / unity multiplier
Brown	1	×10^1	±1%	100 ppm/°C	Precision resistor common
Red	2	×10^2	±2%	50 ppm/°C	General precision use
Orange	3	×10^3	—	15 ppm/°C	Low drift tempco band
Yellow	4	×10^4	—	25 ppm/°C	High multiplier for larger values
Green	5	×10^5	±0.5%	—	Tighter tolerance range
Blue	6	×10^6	±0.25%	10 ppm/°C	Precision analog circuits
Violet	7	×10^7	±0.1%	5 ppm/°C	High-precision designs
Gray	8	×10^8	±0.05%	—	Very tight tolerance
White	9	×10^9	—	—	Highest digit mapping
Gold	—	×10^-1	±5%	—	Tolerance + fractional multiplier
Silver	—	×10^-2	±10%	—	Wide tolerance / low-cost parts

Note: Temperature coefficient values appear only on 6-band resistors and represent resistance drift per degree Celsius.

How to Identify Resistor Orientation

Many axial resistors look symmetric at first glance. Orientation becomes clear when you check spacing and tolerance band style.

1. Find the tolerance band first. It is usually gold, silver, brown, red, or another precision color.
2. Start reading from the opposite side of the tolerance band.
3. If spacing is ambiguous, use the visual calculator preview to verify pattern and decoded value.

Practical Decode Examples

4-band example

Bands: Yellow, Violet, Red, Gold

Decoded: 4.7 kΩ ±5%

Common value for pull-up, signal biasing, and LED support circuits.

5-band example

Bands: Brown, Black, Black, Red, Brown

Decoded: 10 kΩ ±1%

Typical precision value in analog front-end and control feedback paths.

6-band example

Bands: Brown, Black, Black, Red, Brown, Red

Decoded: 10 kΩ ±1% 50 ppm/°C

Suitable where long-term drift and thermal stability matter.

Tolerance and Tempco Selection Matrix

Choose tolerance and ppm/°C levels based on circuit sensitivity, operating temperature range, and lifecycle drift requirements.

Scenario	Tolerance Target	Tempco Target	Design Guidance
General logic and non-critical control	±5% to ±10%	Not critical	4-band parts are usually sufficient and cost-effective.
Industrial analog input / signal conditioning	±1% to ±0.5%	50 to 100 ppm/°C	Prefer 5-band parts for repeatability between channels.
Precision sensing, reference, and instrumentation	±0.25% to ±0.05%	5 to 25 ppm/°C	Use 6-band parts to control temperature drift over lifecycle.