471 capacitor value
470 pF
470 pF · 0.47 nF · 0.00047 µF
| Marked code | 471 |
| Picofarads | 470 pF |
| Nanofarads | 0.47 nF |
| Microfarads | 0.00047 µF |
| Farads | 4.70e-10 F |
Reading the code
The three digits are not a part number. The first two are the value in picofarads and the third says what to do with them:
47 × 101 = 470 pF
So 471 is 47 followed by 1 zero: 470 pF. The code is always in picofarads even when the part is sold in microfarads, which is the whole difficulty with it — a capacitor marked 471 is stocked as 0.00047 µF and the two numbers look nothing alike.
What 470 pF does at frequency
A capacitor's opposition to a signal is its reactance, 1 ÷ (2πfC), and it falls as the frequency rises. Over the range of frequencies a circuit can put across it, a 470 pF part covers several orders of magnitude:
| Frequency | Reactance |
|---|---|
| 50 Hz — mains | 6.77 MΩ |
| 1 kHz — audio | 338.63 kΩ |
| 100 kHz — switching | 3.39 kΩ |
| 10 MHz — RF | 33.86 Ω |
Ten times the frequency is a tenth of the reactance, every time — which is why choosing a decoupling capacitor is really choosing the frequency band you want it to be low-impedance across, and why boards carry several sizes in parallel rather than one large one.
The letter after the number
A code like 471K carries a tolerance letter. It is not part of the value:
| Letter | Tolerance | 470 pF means |
|---|---|---|
471J | ±5% | 446.5 pF to 493.5 pF |
471K | ±10% | 423 pF to 517 pF |
471M | ±20% | 376 pF to 564 pF |
471Z | +80% / −20% | 376 pF to 846 pF |
A Z is worth knowing about. +80%/−20% is a real tolerance on cheap high-permittivity ceramics, and it means a part marked 471Z can legitimately be anything from 376 pF to 846 pF. Those go in decoupling positions where only the rough size matters, never in a timing or filter position.
Where 470 pF turns up
Hundreds of picofarads is filtering at radio frequencies and the timing element in fast oscillators. Below a nanofarad, a ceramic capacitor is close to ideal — very little loss, very little drift — which is why this range is used where accuracy matters.
Frequently asked questions
What is the value of a 471 capacitor?
470 pF — 470 pF · 0.47 nF · 0.00047 µF. The first two digits are the value in picofarads and the third is how many zeros follow, so 471 is 47 followed by 1 zero = 470 pF.
What is a 471 capacitor in µF?
0.00047 µF. Going from picofarads to microfarads is six decimal places, which is where most of the confusion with these codes comes from — 470 pF, 0.47 nF and 0.00047 µF are the same capacitor written three ways.
What does the letter after 471 mean?
Tolerance. 471K is ±10%, 471J is ±5% and 471M is ±20% — so a 471K is anywhere from 423 pF to 517 pF and still in specification. A Z means +80%/−20%, which is not a mistake: some ceramic dielectrics really are that loose.
What is the impedance of a 471 capacitor at 1 kHz?
338.63 kΩ. Reactance is 1 ÷ (2πfC), so it falls as the frequency rises: the same part is 3.39 kΩ at 100 kHz and 33.86 Ω at 10 MHz.
Nearby codes
- 561 capacitor — 560 pF
- 681 capacitor — 680 pF
- 821 capacitor — 820 pF
- 102 capacitor — 1 nF
- 122 capacitor — 1.2 nF
- 152 capacitor — 1.5 nF
- 182 capacitor — 1.8 nF
- 222 capacitor — 2.2 nF
- 272 capacitor — 2.7 nF
- 332 capacitor — 3.3 nF