1 Ω resistor colour code
Four bands: Brown · Black · Gold · Gold. The first two give the digits, the third multiplies, the fourth states how far off the real part may be.
Nominal
1 Ω
1 ohms
Real range at ±5%
0.95 Ω – 1.05 Ω
A gold band allows this much drift.
Series
E6
Held in almost every parts drawer.
Band by band
| Band | Colour | Meaning |
|---|---|---|
| 1 | Brown | 1st digit — 1 |
| 2 | Black | 2nd digit — 0 |
| 3 | Gold | Multiplier — ×0.1 |
| 4 | Gold | Tolerance — ±5% |
How much it can take
Current and dissipation across the resistor, and the package you need. The suggested rating keeps a factor of two in hand, which is what anyone building a board actually does.
| Across it | Current | Dissipated | Package to pick |
|---|---|---|---|
| 3.3 V | 3.3 A | 10.9 W | no standard part — needs a power resistor or a heatsink |
| 5 V | 5 A | 25 W | no standard part — needs a power resistor or a heatsink |
| 12 V | 12 A | 144 W | no standard part — needs a power resistor or a heatsink |
| 24 V | 24 A | 576 W | no standard part — needs a power resistor or a heatsink |
What you can actually get
Parts made
159
117th most of 1,465 values
In stock
939,269
across 12 of them
Cheapest at 100
$0.0024
each
Tolerances sold
±0.1% to ±10%
7 grades in all
Packages: 0805, 0402, 0603, 1210, 1206, 2512, 2010, 0201. Ratings: 50mW to 100W.
Assembly stock from the JLCPCB library, read 2026-09-24. That is what a board house will place for you — not everything a distributor sells.
The same value, marked differently
Surface mount
100· three-digit, nearest only
1000· four-digit, precision parts
01A· EIA-96, for the smallest parts
Three digits carry two significant figures, so they cannot write 1 Ω — 100 means 10 Ω. A part at this value is marked 1000.
Five bands
BrownBlackBlackGoldBrown
Three significant digits and a ±1% band.
Values that can overlap this one
At ±5% the tolerance bands of neighbouring values run into each other. A part sold as one of these could measure the same as a 1 Ω — which is why measuring beats reading when it matters.
If you do not have one
Standard values that land within 1% of 1 Ω when combined.