0.18 Ω resistor colour code
Four bands: Brown · Grey · Silver · Gold. The first two give the digits, the third multiplies, the fourth states how far off the real part may be.
Below 1 Ω a resistor stops being a resistor in the usual sense. Values like this sit in series with a load so a circuit can measure the current through them, or they limit inrush. The silver multiplier band is what takes the value under one ohm — and nothing takes it below 0.1 Ω, because no colour means ×0.001. Smaller shunts exist; their value is printed on the body instead.
Nominal
0.18 Ω
0.18 ohms
Real range at ±5%
0.171 Ω – 0.189 Ω
A gold band allows this much drift.
Series
E12
A current-sense value. Rarely in a hobby parts drawer.
Band by band
| Band | Colour | Meaning |
|---|---|---|
| 1 | Brown | 1st digit — 1 |
| 2 | Grey | 2nd digit — 8 |
| 3 | Silver | Multiplier — ×0.01 |
| 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 | 18.3 A | 60.5 W | no standard part — needs a power resistor or a heatsink |
| 5 V | 27.8 A | 139 W | no standard part — needs a power resistor or a heatsink |
| 12 V | 66.7 A | 800 W | no standard part — needs a power resistor or a heatsink |
| 24 V | 133 A | 3200 W | no standard part — needs a power resistor or a heatsink |
What you can actually get
Standard on paper, absent from the shelf.
0.18 Ω is a proper E12 value, but no part carrying it is currently held for assembly.
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
If you do not have one
Standard values that land within 1% of 0.18 Ω when combined.