0.3 Ω resistor colour code
Four bands: Orange · Black · 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
0.3 Ω
0.3 ohms
Real range at ±5%
0.285 Ω – 0.315 Ω
A gold band allows this much drift.
Series
E24
A current-sense value. Rarely in a hobby parts drawer.
Band by band
| Band | Colour | Meaning |
|---|---|---|
| 1 | Orange | 1st digit — 3 |
| 2 | Black | 2nd digit — 0 |
| 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 | 11 A | 36.3 W | no standard part — needs a power resistor or a heatsink |
| 5 V | 16.7 A | 83.3 W | no standard part — needs a power resistor or a heatsink |
| 12 V | 40 A | 480 W | no standard part — needs a power resistor or a heatsink |
| 24 V | 80 A | 1920 W | no standard part — needs a power resistor or a heatsink |
What you can actually get
Standard on paper, absent from the shelf.
0.3 Ω is a proper E24 value, but no part carrying it is currently held for assembly. The nearest value you will actually find is 0.287 Ω.
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
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 0.3 Ω — which is why measuring beats reading when it matters.
If you do not have one
Standard values that land within 1% of 0.3 Ω when combined.