Having trouble?
Go to tutorial
📝 How it works:
Calculate charge and energy of a capacitor for a given capacitance and voltage.
Fill in the fields below and click "Calculate".
Calculate charge and energy of a capacitor for a given capacitance and voltage.
Fill in the fields below and click "Calculate".
Capacitor Calculator - Free Online Tool
Calculate capacitance, voltage and energy in capacitors Our calculator provides fast, accurate, and free calculations for your needs.
How to Use Capacitor Calculator
Simply enter your values and get instant results. No registration required, works on all devices.
Key Features
- Accurate Results: Mathematically precise calculations
- Free to Use: No limits, no ads, no registration
- Mobile Friendly: Works on smartphones and tablets
- Instant Results: Real-time calculations
Why Use Our Capacitor Calculator?
Trusted by thousands of users daily. Fast, reliable, and always available. Perfect for professional and personal use.
Charge and energy of typical capacitors
Calculated with Q = C × V and E = ½ × C × V² at the stated voltage:
| Capacitance | Voltage | Charge Q | Energy E |
|---|---|---|---|
| 10 µF | 400 V | 4.00 mC | 800.0 mJ |
| 100 µF | 25 V | 2.50 mC | 31.2 mJ |
| 470 µF | 35 V | 16.4 mC | 287.9 mJ |
| 1,000 µF | 16 V | 16.0 mC | 128.0 mJ |
| 2,200 µF | 25 V | 55.0 mC | 687.5 mJ |
| 4,700 µF | 63 V | 296.1 mC | 9.33 J |
| 1 F (supercap) | 2.7 V | 2.70 C | 3.65 J |
| 10 F (supercap) | 2.7 V | 27.0 C | 36.5 J |
RC time constant τ = R × C
After one τ the capacitor is charged to about 63 %, after 5τ practically fully (over 99 %).
| Resistance | Capacitance | τ | 5τ (fully charged) |
|---|---|---|---|
| 1 kΩ | 100 µF | 0.100 s | 0.50 s |
| 10 kΩ | 10 µF | 0.100 s | 0.50 s |
| 10 kΩ | 100 µF | 1.000 s | 5.00 s |
| 47 kΩ | 22 µF | 1.034 s | 5.17 s |
| 100 kΩ | 10 µF | 1.000 s | 5.00 s |
| 1 MΩ | 1 µF | 1.000 s | 5.00 s |
