Circuit Toolkit
Engineering calculators and circuit builders — free, no login, no installation. Each one is a focused single-job tool you can use alongside the topic pages or on its own for a quick answer.
43 of 43 tools
Component codes
3 toolsDC fundamentals
4 toolsOhm's Law Calculator
V, I, R, P — any two in, everything out.
Resistor Network Solver
Series, parallel or mixed — wire a resistor network and it solves itself.
KVL Loop Solver
Up to 3 sources with polarity toggles — live KVL equation and solved current.
KCL Node Analyzer
Set branch currents and directions — live KCL equation at a node.
Digital logic
13 toolsDigital Number Systems Lab
Convert, toggle bits, trace every step — or test yourself in practice mode.
Logic Circuit Lab
Build gate networks, watch signal flow, and explore Boolean algebra from circuit to K-map.
Boolean Simplifier
Type an expression — apply identities and watch it shrink.
SOP / POS Builder & K-Map Solver
Truth table + K-map of the same function — canonical Σm/ΠM above, minimum SOP/POS below.
Quine–McCluskey Reducer
Tabular minimisation — iteration columns, PI chart, and minimum SOP.
Universal Gate Builder
Build NOT / AND / OR / XOR / XNOR from NAND-only or NOR-only gates.
Adder & Subtractor
Half / full adder up to 4-bit signed add-subtract with overflow flag.
Combinational Blocks
4:1 MUX, 2-to-4 decoder, and 4-bit comparator — toggle between blocks.
Static Hazard Analyzer
Watch a static-1 glitch on F = AB + A'C — add the consensus cover to kill it.
Flip-Flop Simulator
D, JK, T, SR, SR active-low — toggle inputs, watch waveforms, see excitation tables.
Timing Analyzer
Adjust setup / hold / propagation delay — watch violations and max-frequency update live.
Register & Shift Register
SISO, SIPO, PISO, PIPO shift modes — clock data through and watch each stage.
Ripple Counter Explorer
MOD-2 to MOD-16 — watch the domino ripple, timing waveforms, and frequency division.
AC & signals
7 toolsCapacitor Network Combiner
Series / parallel caps — live equivalent and schematic.
Inductor Network Combiner
Series / parallel inductors — live equivalent inductance and schematic.
Impedance Builder
R + jX on the complex plane — triangle flips through resonance.
Waveform Lab
Sine, triangle, sawtooth, square — Vp, Vpp, Vrms and T marked on the trace.
Phasor Playground
Two rotating vectors, their sines, and the lag between them.
Reactance Plotter
Capacitive or inductive reactance versus frequency — log-log sweep with a marker.
RC / LR Transient Plotter
Charge, discharge, time constant — the first-order curve.
Filters & frequency
1 toolPower & energy
6 toolsTransformer Playground
Turn ratio, MMF balance, and live V / I on an ideal transformer.
Regulator Compare
Linear vs switching — efficiency, power loss, and heatsink verdict live.
SCR Controlled Rectifier
Drag the firing angle and watch the half-wave output reshape in real time.
DC-DC Converter
Buck, boost, buck-boost — switch node voltage, ON/OFF shading, slope equations, CCM/DCM live.
Inverter
H-bridge switching states, harmonic spectrum, current waveform, SPWM carrier — all live.
Power Factor Analyzer
Displacement vs distortion PF, harmonic spectrum, before/after PFC comparison — live.
Semiconductors
8 toolsDiode Lab
I-V plotter, half-wave, full-wave (bridge / center-tapped) — one widget.
Zener Regulator Playground
Live Zener regulator + 4-curve compare (Zener / LED / Schottky / photodiode).
BJT Simulator
Switch (cutoff / active / saturation) + Q-point stability across β and temperature.
FET Simulator
JFET (Shockley) and MOSFET (square-law) transfer and output curves side by side.
Op-Amp Calculator
9 configurations — gain formula, circuit schematic, and live waveform in one card.
Transistor Bias Explorer
DC bias → small-signal equivalent — hybrid-π (BJT) and FET models with Q-point coach.
CE / CS Amplifier Bench
Design a common-emitter or common-source stage — bias, load line, gain, impedance.
Differential Pair Playground
Sweep the differential input and watch current redistribute — gains and CMRR live.