561 capacitor value
560 pF
560 pF · 0.56 nF · 0.00056 µF
| Marked code | 561 |
| Picofarads | 560 pF |
| Nanofarads | 0.56 nF |
| Microfarads | 0.00056 µF |
| Farads | 5.60e-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:
56 × 101 = 560 pF
So 561 is 56 followed by 1 zero: 560 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 561 is stocked as 0.00056 µF and the two numbers look nothing alike.
What 560 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 560 pF part covers several orders of magnitude:
| Frequency | Reactance |
|---|---|
| 50 Hz — mains | 5.68 MΩ |
| 1 kHz — audio | 284.21 kΩ |
| 100 kHz — switching | 2.84 kΩ |
| 10 MHz — RF | 28.42 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 561K carries a tolerance letter. It is not part of the value:
| Letter | Tolerance | 560 pF means |
|---|---|---|
561J | ±5% | 532 pF to 588 pF |
561K | ±10% | 504 pF to 616 pF |
561M | ±20% | 448 pF to 672 pF |
561Z | +80% / −20% | 448 pF to 1.008 nF |
A Z is worth knowing about. +80%/−20% is a real tolerance on cheap high-permittivity ceramics, and it means a part marked 561Z can legitimately be anything from 448 pF to 1.008 nF. Those go in decoupling positions where only the rough size matters, never in a timing or filter position.
Where 560 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 561 capacitor?
560 pF — 560 pF · 0.56 nF · 0.00056 µF. The first two digits are the value in picofarads and the third is how many zeros follow, so 561 is 56 followed by 1 zero = 560 pF.
What is a 561 capacitor in µF?
0.00056 µF. Going from picofarads to microfarads is six decimal places, which is where most of the confusion with these codes comes from — 560 pF, 0.56 nF and 0.00056 µF are the same capacitor written three ways.
What does the letter after 561 mean?
Tolerance. 561K is ±10%, 561J is ±5% and 561M is ±20% — so a 561K is anywhere from 504 pF to 616 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 561 capacitor at 1 kHz?
284.21 kΩ. Reactance is 1 ÷ (2πfC), so it falls as the frequency rises: the same part is 2.84 kΩ at 100 kHz and 28.42 Ω at 10 MHz.
Nearby codes
- 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
- 392 capacitor — 3.9 nF