Resistor Color Code Calculator — bands to resistance

How it works

Resistors are marked with colored bands under the IEC 60062 / EIA color code. On a common 4-band resistor:

• Band 1 and Band 2 are the first two significant digits (black 0, brown 1, red 2, orange 3, yellow 4, green 5, blue 6, violet 7, grey 8, white 9)
• Band 3 is the multiplier — a power of ten (black ×1, brown ×10, red ×100, … plus gold ×0.1 and silver ×0.01 for small values)
• Band 4 is the tolerance — how far the real value may vary (brown ±1%, red ±2%, gold ±5%, silver ±10%)

The resistance is (digit1 × 10 + digit2) × multiplier, and the tolerance sets the minimum and maximum. Read the bands with the tolerance band (often gold or silver, and slightly set apart) on the right.

Worked example

Yellow, Violet, Red, Gold:

• Digits: yellow = 4, violet = 7 → 47
• Multiplier: red = ×100 → 47 × 100 = 4,700 Ω (4.7 kΩ)
• Tolerance: gold = ±5% → between 4,465 Ω and 4,935 Ω

Frequently asked questions

Which end do I read from?

Start from the band nearest an end and read toward the tolerance band, which is usually gold or silver and set a little apart from the others. If neither end has a gold/silver band, the tolerance band is the one closest to an edge.

What do gold and silver mean?

As a **multiplier**, gold is ×0.1 and silver is ×0.01 — used for resistances below 10 Ω. As a **tolerance**, gold is ±5% and silver is ±10%, the most common tolerances.

What is tolerance?

It's how much the actual resistance may differ from the marked value. A 4,700 Ω ±5% resistor is guaranteed only to be within 4,465–4,935 Ω, so precision circuits use tighter tolerances (±1% or better).

What about 5-band and 6-band resistors?

5-band resistors add a third digit band for more precision, and 6-band ones add a temperature coefficient. This calculator covers the common 4-band type; for a 5-band, the first three bands are digits.

Why is there no band for 0 Ω?

A single black band marks a **zero-ohm** resistor (a jumper). In the normal code, black as a digit is 0 and as a multiplier is ×1.

How do I read the value in kΩ or MΩ?

Resistances are usually written with a metric prefix to keep them short: **1 kΩ = 1,000 Ω**, **1 MΩ = 1,000,000 Ω**, and **1 GΩ = 1,000,000,000 Ω**. So a decoded value of 4,700 Ω is **4.7 kΩ**, and 2,200,000 Ω is **2.2 MΩ**. This calculator shows the resistance with its metric prefix already applied — for example **4.7k** under the "Resistance (Ω)" label means 4.7 kΩ — so you can read it straight off.