Electronics & Circuits calculators
Reactance, filters, 555 timers, op-amps, PCB traces, RF, batteries and digital logic.
39 free tools
Most used
555 Timer CalculatorFrequency, duty cycle and pulse width for 555 astable and monostable circuitsdBm to Watts ConverterConvert dBm, dBW, watts and milliwatts — plus RMS voltage at 50 ΩLC Resonant Frequency CalculatorResonant frequency of an LC tank — or the L or C needed for a target frequencymAh to Wh ConverterConvert battery capacity between mAh, Ah and watt-hoursOp-Amp Gain CalculatorGain, dB and output voltage for inverting, non-inverting and difference ampsPC Power Supply CalculatorEstimate your PC’s power draw and the PSU wattage to buyPCB Trace Width CalculatorMinimum PCB trace width for your current using the IPC-2221 formulaRC Filter CalculatorCutoff frequency, gain and phase of RC low-pass and high-pass filtersRLC Impedance CalculatorImpedance, phase angle and reactance of series and parallel RLC circuitsRMS Voltage CalculatorConvert between peak, peak-to-peak, RMS and average voltage for any waveformTransformer Turns Ratio CalculatorTurns ratio, secondary voltage, currents and reflected impedanceTruth Table GeneratorInstant truth tables, minterms and canonical forms for any logic expression
More electronics & circuits tools
ADC Resolution CalculatorLSB size, output code, ideal SNR and Nyquist limits for any ADCAntenna Length CalculatorCut lengths for dipole, quarter-wave, 5/8-wave and loop antennasBattery Charge Time CalculatorHow long a battery takes to charge from its capacity and charger currentBattery Pack CalculatorVoltage, capacity, energy and current of series-parallel cell packsBoolean Algebra SimplifierMinimise any logic expression to its simplest SOP and POS formsCapacitive Reactance CalculatorFind Xc from capacitance and frequency — or solve for C or fCapacitor Code CalculatorDecode markings like 104, 4n7 or 2A473J into pF, nF and µFCoax Cable Loss CalculatorSignal loss in dB and power delivered for RG-58, RG-213, LMR-400 and moreFree Space Path Loss CalculatorFSPL, received signal strength and link margin for any radio linkHeatsink CalculatorRequired heatsink thermal resistance and resulting junction temperatureInductive Reactance CalculatorFind XL from inductance and frequency, or solve for L or fLED Strip Power CalculatorPower supply size, current and feed-wire voltage drop for LED stripsLM317 Voltage Regulator CalculatorPick R1 and R2 for an LM317 output voltage, with standard values and heatPWM Duty Cycle CalculatorDuty cycle, pulse width, frequency and average voltage of a PWM signalRL Time Constant CalculatorTime constant, current rise and decay of a series RL circuitSMD Resistor Code CalculatorDecode 3-digit, 4-digit and EIA-96 SMD resistor markings — or encode themTransistor Base Resistor CalculatorSize the base resistor to switch a BJT fully on from a GPIO pinVSWR CalculatorConvert VSWR, return loss, reflection coefficient and mismatch lossWire Resistance CalculatorResistance, voltage drop and power loss of copper or aluminum wireZener Diode CalculatorSize the series resistor and power ratings for a zener voltage regulatorAir Core Inductor CalculatorInductance of a single-layer air coil, or the turns needed for a targetCrystal Load Capacitor CalculatorPick the right load capacitors for a Pierce crystal oscillatorInductor Color Code CalculatorDecode the colour bands on axial inductors into microhenriesKarnaugh Map SolverMinimise Boolean functions of 2–6 variables to simplest SOP and POSMicrostrip Impedance CalculatorCharacteristic impedance and trace width for PCB microstrip linesStar-Delta Conversion CalculatorConvert resistor networks between delta (Δ) and star/wye (Y) formWheatstone Bridge CalculatorFind the unknown resistor, bridge output voltage and meter current