RC charging and discharging
Explore capacitor voltage over time, time to a target voltage and the RC time constant. Drag the graph handles to change inputs and explore the result.
Your inputs
Example values are editable. Use your measurements and product specifications. Results update as you edit.
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How it works
- τ = × ; Vcharge() = × (1 − e^(−/τ)); Vdischarge() = × e^(−/τ)
- tcharge = −τ × ln(1 − /); tdischarge = −τ × ln(/)
- fc = 1 / (2π)
Input and formula key
Your result
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Assumptions and limitations
Ideal single RC circuit with constant resistance and capacitance. Charging starts at 0 V toward the entered supply; discharging starts at the entered initial voltage toward 0 V. Endpoints are asymptotic. Cutoff is for a first-order RC filter. With 10 kΩ and 100 µF, τ = 1 s.
Sources
- OpenStax — circuits and RC circuits Sources reviewed: 2026-10-10
