Resistor Color Code

Convert between resistor color bands and resistance values. Select colors or enter a value.

Color Code Reference

Color	Digit	Multiplier	Tolerance

Standard Values (E Series)

Resistors come in standard "E series" values. The number indicates how many values per decade (10× range). Each series corresponds to a tolerance - tighter tolerance needs more values to cover all possible targets.

E12 (±10%) - 12 values per decade

1.0, 1.2, 1.5, 1.8, 2.2, 2.7, 3.3, 3.9, 4.7, 5.6, 6.8, 8.2

E24 (±5%) - 24 values per decade

1.0, 1.1, 1.2, 1.3, 1.5, 1.6, 1.8, 2.0, 2.2, 2.4, 2.7, 3.0, 3.3, 3.6, 3.9, 4.3, 4.7, 5.1, 5.6, 6.2, 6.8, 7.5, 8.2, 9.1

E48 (±2%) - 48 values per decade

Adds intermediate values: 1.05, 1.15, 1.27, 1.37, 1.47, 1.62, 1.74, 1.87, 2.05, ...

E96 (±1%) - 96 values per decade

Fine-grained values for precision applications. Typically 5-band resistors.

Example: In E24, after 4.7kΩ comes 5.1kΩ, then 5.6kΩ. You won't find a 5.0kΩ resistor - use 5.1kΩ or combine values (4.7kΩ + 330Ω in series, or two 10kΩ in parallel).

Resistor Types

Different construction methods offer different trade-offs in precision, noise, temperature stability, and power handling.

Carbon Film

Thin carbon layer on ceramic. Cheap, general purpose. ±5% tolerance typical.

Use for: Non-critical applications, pull-ups/pull-downs, LED current limiting, hobby projects.

Avoid for: Audio signal paths (noisy), precision circuits.

Metal Film

Thin metal alloy layer. Low noise, good temperature stability. ±1% typical.

Use for: Audio circuits, precision voltage dividers, instrumentation, anywhere noise matters.

Note: The go-to choice for most applications. Only slightly more expensive than carbon film.

Metal Oxide

Thicker metal oxide coating. Better power handling and surge resistance than metal film.

Use for: Power supplies, surge protection, high-temperature environments.

Wirewound

Resistive wire wound on ceramic core. Excellent power handling, very precise, but inductive.

Use for: High-power applications (5W+), current sensing, precision references.

Avoid for: High-frequency circuits (inductance causes problems above ~50kHz).

Thick Film (SMD)

Printed resistive paste on ceramic substrate. Standard surface-mount type.

Use for: Production PCBs, space-constrained designs. Available in 0402, 0603, 0805, 1206 packages.

Note: 0603 (1.6×0.8mm) is a good balance of size and hand-solderability.

Thin Film (SMD)

Sputtered metal layer on ceramic. Superior precision and temperature coefficient.

Use for: Precision instrumentation, matched resistor networks, low-noise audio.

Note: ±0.1% tolerance and 25ppm/°C tempco available. More expensive.

Rule of thumb: Use metal film for through-hole, thick film 0603 for SMD. Only go fancier when you have a specific reason (precision, power, noise, temperature).