Can I use a multimeter instead?

Yes, measure resistance directly with probes on each lead.

Science

Resistor Color Code Calculator

Decode resistor color bands to find resistance value and tolerance. Supports 4, 5, and 6 band resistors.

Quick Answer

Read bands left to right: first bands are digit values, second-to-last is the multiplier, last band is tolerance. Brown-Black-Red-Gold = 10 × 100 = 1kΩ ±5%.

Number of Bands

Band 1 (1st digit)

Band 2 (2nd digit)

Multiplier

Tolerance

Results

1 kΩ

Resistance

±10%

Tolerance

900 Ω–1.10 kΩ

Range

About This Tool

The Resistor Color Code Calculator decodes the colored bands on through-hole resistors to determine their resistance value and tolerance. It supports 4-band (standard), 5-band (precision), and 6-band (precision with temperature coefficient) resistors.

Reading Color Bands

Hold the resistor with the tolerance band (gold or silver) on the right. Read from left to right. The first 2 (or 3) bands are significant digits. The next band is the multiplier (number of zeros). The last band is tolerance. For 6-band resistors, the sixth band is the temperature coefficient.

The Color Code Table

Black=0, Brown=1, Red=2, Orange=3, Yellow=4, Green=5, Blue=6, Violet=7, Grey=8, White=9. For multiplier: Gold=0.1, Silver=0.01. For tolerance: Brown=1%, Red=2%, Green=0.5%, Blue=0.25%, Violet=0.1%, Grey=0.05%, Gold=5%, Silver=10%.

4-Band vs 5-Band Resistors

4-band resistors have two significant digits (giving 2-digit precision like 47, 10, 22). 5-band resistors have three significant digits for better precision (like 100, 470, 221). Higher-precision circuits use 5-band or SMD resistors with numeric markings.

Tolerance Matters

A 1kΩ ±5% resistor actually ranges from 950Ω to 1050Ω. For precision applications like voltage dividers, instrumentation amplifiers, or timing circuits, use 1% or better tolerance. For pull-up resistors and current limiters, 5% is typically fine.

Frequently Asked Questions

Which end do I start reading from?

Start from the end with bands grouped closer together. The tolerance band (gold/silver) is usually separated by a slightly wider gap and should be on the right. If unsure, look for gold or silver — that's the tolerance band.

What does a gold band mean?

As the multiplier band: multiply by 0.1 (for sub-1-ohm resistors). As the tolerance band: ±5% tolerance, which is the most common standard tolerance.

How do I read a 5-band resistor?

Three significant digit bands, then multiplier, then tolerance. Brown-Black-Black-Red-Brown = 100 × 100 = 10kΩ ±1%.

What are standard resistor values?

Resistors come in standard E-series values. E12 (±10%): 10, 12, 15, 18, 22, 27, 33, 39, 47, 56, 68, 82. E24 (±5%) adds intermediate values. E96 (±1%) provides 96 values per decade.

Can I measure resistance with a multimeter instead?

Yes, and it's more accurate for identifying unknown resistors. Set your multimeter to the ohms setting, touch the probes to each lead, and read the value. Make sure the resistor is not in a circuit when measuring.

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