10 nF capacitor (0.01 µF)
A 10 nF capacitor is the same as 0.01 µF or 10,000 pF. On ceramic and film parts it is printed as the code 103; schematics often write 10n.
How a 10 nF capacitor is marked
| Style | Marking | Where you see it |
|---|---|---|
| 3-digit code | 103 | Ceramic discs, multilayer ceramics, film capacitors |
| Code + tolerance | 103J · 103K · 103M | ±5% · ±10% · ±20% |
| Code + voltage | 1H103K · 2A103J | 50 V · 100 V film capacitors |
| IEC 60062 letter code | 10n | Schematics, European parts (the letter is the decimal point) |
| Plain value | .01 (µF) on older parts | Older US parts and electrolytics — bare decimals are µF |
| SMD (0402–1206) | usually unmarked | Check the reel label or measure with an LCR meter |
10 nF in every unit
| Picofarads | 10,000 pF |
|---|---|
| Nanofarads | 10 nF |
| Microfarads | 0.01 µF |
| Farads | 1 × 10^-8 |
Reactance of 10 nF
A capacitor's opposition to AC falls as frequency rises: XC = 1 ÷ (2π f C). This tells you whether 10 nF passes or blocks a signal — a decoupling capacitor needs a low reactance at the noise frequency, a coupling capacitor at the lowest signal frequency.
| Frequency | Reactance XC |
|---|---|
| 50 Hz | 318 kΩ |
| 60 Hz | 265 kΩ |
| 1 kHz | 15.9 kΩ |
| 10 kHz | 1.59 kΩ |
| 100 kHz | 159 Ω |
| 1 MHz | 15.9 Ω |
| 10 MHz | 1.59 Ω |
Real capacitors stop behaving like ideal ones above their self-resonant frequency, which depends on the package and lead length, so treat the high-frequency rows as an upper bound on performance.
RC time constant and filter corner with 10 nF
With a resistor R, the capacitor charges to 63% in one time constant τ = R × C and to over 99% in 5τ. The same pair makes a first-order low-pass or high-pass filter with corner frequency fc = 1 ÷ (2π R C).
| Resistor | τ = RC | 5τ (≈ full charge) | Corner fc |
|---|---|---|---|
| 100 Ω | 1 µs | 5 µs | 159 kHz |
| 1 kΩ | 10 µs | 50 µs | 15.9 kHz |
| 10 kΩ | 100 µs | 500 µs | 1.59 kHz |
| 100 kΩ | 1 ms | 5 ms | 159 Hz |
Choosing a 10 nF capacitor
| Usual dielectric | X7R ceramic, polyester (PET) film |
|---|---|
| Common voltage ratings | 50–100 V |
| Neighbouring E6 values | 3.3 nF, 4.7 nF, 6.8 nF, 15 nF, 22 nF, 33 nF |
10 nF is the classic value for a 555 timer control-voltage pin and for RC snubbers. Old ceramic discs often print .01 instead of 103 — that is 0.01 µF, the same value. X7R ceramic is fine for decoupling; use film or C0G when the value sets a frequency.
FAQ
What is the code for a 10 nF capacitor?
103. The first two digits (10) are picofarads and the third (3) is the number of zeros: 10,000 pF. In IEC letter notation it is written 10n.
Is 10 nF the same as 0.01 µF?
Yes. 10,000 pF = 10 nF = 0.01 µF; they are three names for the same capacitance.
What is the reactance of a 10 nF capacitor?
Xc = 1 ÷ (2π × f × C). At 1 kHz a 10 nF capacitor has 15.9 kΩ; at 50 Hz 318 kΩ.
What cutoff frequency does 10 nF give with 10 kΩ?
fc = 1 ÷ (2π × 10 kΩ × 10 nF) = 1.59 kHz, and the time constant τ = R × C = 100 µs.