Resistor Color Code Calculator (4 / 5 band)
Pick the colour bands you see on the resistor and the calculator instantly returns the resistance (Ω / kΩ / MΩ), the tolerance and the actual min/max range. It also reports the nearest E12 / E24 preferred value so you can quickly check whether a non-stocked value can be substituted with a standard part. Both the 4-band (5% / 10% commodity) and 5-band (1% / 2% precision) notations are supported, all per IEC 60062.
Pick a colour for every band to decode the resistor.
Resistance
4.7 kΩ
Tolerance
±5%
Actual range
4.465 kΩ – 4.935 kΩ
Nearest E-series preferred value
—
Encoding follows IEC 60062. In practice, ageing, lighting and ink quality can blur red ↔ orange or violet ↔ blue — verify questionable parts with a multimeter.
Formula
4-band: R = (D₁D₂) × 10^M 5-band: R = (D₁D₂D₃) × 10^M D = digit band (black 0, brown 1, red 2, orange 3, yellow 4, green 5, blue 6, violet 7, grey 8, white 9) M = multiplier band (black 0, brown 1, red 2, orange 3, yellow 4, green 5, blue 6, violet 7, grey 8, white 9, gold −1, silver −2) Tolerance band: brown ±1%, red ±2%, green ±0.5%, blue ±0.25%, violet ±0.1%, grey ±0.05%, gold ±5%, silver ±10%
- · Colour encoding follows IEC 60062:2016 (formerly EIA RS-279). All mainstream catalogues (Vishay, Yageo, Panasonic, KOA) use the same assignment.
- · Reading direction: the tolerance band (most often gold or silver) is usually offset further from the others — start from the opposite end and you cannot read the resistor backwards.
- · E12 (5% / 10% commodity) has 12 mantissas 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 doubles that density (1.0, 1.1, 1.2, 1.3 …). E96 (1%) is normally a 5-band part.
- · In a 4-band resistor, gold and silver as the multiplier mean ×0.1 and ×0.01 respectively — common for sub-ohm parts such as a 0.47 Ω current-limiting resistor.
- · In real life red ↔ orange and violet ↔ blue blur quickly under poor lighting or with aged ink. When in doubt, measure with a multimeter — that is the authoritative reading.
- · This tool decodes the colour bands of fixed-value carbon-film / metal-film through-hole resistors only. Surface-mount 0805 / 0603 chips use a 3- or 4-digit numeric code instead.
Frequently asked
How do I tell which end to start reading from?
Three quick checks: (1) the tolerance band on the right is usually visibly offset further from the other bands; (2) gold or silver only appear as tolerance / multiplier bands, so a gold or silver band is almost always the last band; (3) the first band typically sits near a lead. If none of those help, decode in both directions and pick the one that lands on a standard E12 / E24 value — the other will be a meaningless number.
What is the difference between 4-band and 5-band resistors?
4-band parts encode two significant digits (e.g. 4.7, 6.8) and are typically ±5% or ±10% — fine for LED current limiting, pull-ups, signal dividers and most hobby work. 5-band parts encode three significant digits (e.g. 4.99, 6.81) and are typically ±1% or ±2% — used in measurement circuits, instrumentation, op-amp gain setting and anywhere a tight ratio matters.
I decoded a value (e.g. 5.0 kΩ) but cannot find that resistor on sale — why?
Manufacturers only stock E-series mantissas. 5,000 Ω is not in E12 or E24, so it simply is not produced as a discrete part — you would substitute the nearest preferred value (4.7 kΩ in E12 or 5.1 kΩ in E24, both shown by the "nearest E-series" line above). If your decoded value still looks unusual after that, double-check the bands you read — red and orange are the most common colour confusion under poor lighting.
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