Start here 1
Reduce a passive network
Find equivalent resistance, capacitance, or inductance before calculating current, energy, timing, or resonance.
Open RLC network calculator
Calculator hub
Timing and passive component calculators
Equivalent RLC networks, reactance, resonance, RC and LR settling, capacitor discharge, and 555 timing.
Calculator navigation: Choose the right calculator, follow common design paths, and open supporting pages when the calculation needs engineering context.
Start here
Choose by timing or passive-component task
Start with the physical behaviour you need to check, then follow the related calculator or workflow.
Start here 2
Check reactance or resonance
Calculate capacitive reactance, inductive reactance, LC resonance, and series RLC impedance context.
Open reactance calculator
Start here 3
Calculate first-order settling
Use RC or LR time constants for charging, current rise, delays, and settling estimates.
Open RC time constant
Start here 4
Design a 555 timing circuit
Calculate astable frequency and duty cycle or monostable pulse width from timing components.
Open 555 timer calculator
Calculators
Timing and passive component calculators
These calculators cover passive-network reduction, reactance, resonance, first-order settling, discharge, and 555 timing.
Available Tolerance aware
Series and Parallel RLC Network Calculator
Calculate tolerance-aware equivalent resistor, capacitor, or inductor values for ideal series and parallel networks, with resistor current and power outputs.
Available
RLC Reactance and Resonance Calculator
Calculate capacitive reactance, inductive reactance, LC resonant frequency, series RLC impedance, phase, and Q from ideal component values.
Available Tolerance aware
555 Timer Calculator
Calculate 555 timer astable frequency, period, duty cycle, and monostable one-shot pulse width with tolerance-aware timing ranges.
Available Tolerance aware
RC Time Constant Calculator
Calculate RC time constant and capacitor voltage during charge or discharge with engineering notation support.
Available Tolerance aware
LR Time Constant and Settling Calculator
Calculate LR time constant, resistance, inductance, and first-order settling percentages from 1 tau to 5 tau.
Available
Capacitor Discharge Calculator
Calculate capacitor discharge voltage, time to threshold, resistance, capacitance, and RC time constant for bleed paths.
Workflows
Timing and passive-component workflows
Use these paths when one numeric result leads directly to another component, energy, filter, or stress check.
Workflow
RC timing and discharge
Move from time constant into voltage decay and threshold timing.
- 1 RC time constant Calculate tau and first-order voltage behaviour.
- 2 Capacitor discharge Calculate decay or time to threshold.
- 3 RC filter workflow Continue into frequency-domain filter checks.
Workflow
Inductive settling and stored energy
Check the LR response before reviewing the energy that must be switched or clamped.
- 1 LR time constant Calculate current rise and settling.
- 2 Inductor energy Calculate stored magnetic energy.
- 3 Clamp-path guide Review interrupted-current stress.
Workflow
RLC network and resonance
Reduce the network first, then evaluate frequency-dependent behaviour.
- 1 Equivalent RLC network Reduce series or parallel components.
- 2 Reactance and resonance Calculate reactance and LC resonance.
- 3 Filter calculators Continue into a specific filter topology.
Questions
Timing and passive-component FAQ
Use these answers to choose between time-domain, frequency-domain, and stored-energy workflows.
Why are timing and passive components grouped together?
RC, LR, RLC, and 555 timing results depend directly on resistor, capacitor, and inductor values. This hub keeps those time-domain and passive-network checks together while filter design remains in the filters and analogue circuits hub.
Where are capacitor and inductor energy calculators?
Stored-energy calculations are in the power supply and energy hub because their next checks usually involve hold-up, clamps, switching stress, or safety paths.
Where are RC filter calculators?
Use the filters and analogue circuits hub when the design question is cutoff frequency or signal filtering. Use this hub when the main question is charging, settling, delay, discharge, reactance, or resonance.
What this hub does not replace
These calculators use ideal or documented first-order models. Real components and switching circuits still need parasitic, tolerance, saturation, voltage-rating, current-rating, and measurement review.
- Check capacitor ESR, ESL, leakage, dielectric behaviour, and voltage coefficient.
- Check inductor saturation, winding resistance, core loss, and clamp paths.
- Use simulation or measurement when damping, switching, or parasitic coupling controls the result.