51 Ω resistor colour code
Four bands: Green · Brown · Black · Gold. The first two give the digits, the third multiplies, the fourth states how far off the real part may be.
Nominal
51 Ω
51 ohms
Real range at ±5%
48.45 Ω – 53.55 Ω
A gold band allows this much drift.
Series
E24
E24 only — stocked less often.
Band by band
| Band | Colour | Meaning |
|---|---|---|
| 1 | Green | 1st digit — 5 |
| 2 | Brown | 2nd digit — 1 |
| 3 | Black | Multiplier — ×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 | 64.7 mA | 214 mW | 1/2 W |
| 5 V | 98 mA | 490 mW | 1 W |
| 12 V | 235 mA | 2.82 W | no standard part — needs a power resistor or a heatsink |
| 24 V | 471 mA | 11.3 W | no standard part — needs a power resistor or a heatsink |
What you can actually get
Parts made
184
66th most of 1,465 values
In stock
875,770
across 9 of them
Cheapest at 100
$0.0012
each
Tolerances sold
±0.01% to ±5%
7 grades in all
Packages: 0805, 0603, 1206, 1210, 0402, 2010, 1225, 2512. Ratings: 30mW to 50W.
What ten of them actually cost
The price everyone quotes is the reel price. If you want ten, you cannot buy the reel — and the real figure is usually several times higher per piece.
Ten pieces
$0.18
$0.018 each · Cut Tape (CT) · minimum order 1
The reel price
$0.00161
each, but only from 100,000 pieces up
Sitting in stock
3,980,546
across 26 part numbers
Per piece, ten costs 11.2× the reel price. That gap is why a handful of resistors never costs what the headline price suggests.
Stocked in ±0.5% and ±1% and ±5%, rated 1/20 W to 1 W.
Cheapest part you can buy ten of: RMCF0402JT51R0 by Stackpole Electronics Inc — see it at Digi-Key.
Assembly stock from the JLCPCB library, read 2026-09-24. Retail prices and stock from Digi-Key, read 2026-09-24. Prices move — check the product page before ordering. That is what a board house will place for you — not everything a distributor sells.
The same value, marked differently
Five bands
GreenBrownBlackBlackBrown
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 51 Ω — which is why measuring beats reading when it matters.
- 47 Ω44.65 Ω–49.35 Ω
- 48.7 Ω48.213 Ω–49.187 Ω
- 49.9 Ω49.401 Ω–50.399 Ω
- 51.1 Ω50.589 Ω–51.611 Ω
- 52.3 Ω51.777 Ω–52.823 Ω
- 53.6 Ω53.064 Ω–54.136 Ω
- 56 Ω53.2 Ω–58.8 Ω
If you do not have one
Standard values that land within 1% of 51 Ω when combined.