Free online calculator
Resistor ratio calculator

Example R1/R2 = 1
— or with "Invert" ticked.
What you enter
- R1 (Ω)
- R2 (Ω)
- Invert (compute R2 / R1)
Free online calculator

Example R1/R2 = 1
— or with "Invert" ticked.
What you enter
Star / delta transformSome networks — a Wheatstone bridge with a load across the middle is the standard one — have no two resistors in plain series or plain parallel, so the…
Thévenin / NortonAny linear source, however many parts are inside it, behaves at one pair of terminals exactly like a voltage source behind a series resistance — or, just…
Wheatstone bridgeEach half is its own divider, and the output is the difference between their midpoints:
Sallen-Key filterA unity-gain second-order low-pass: sets where it turns, sets the shape. Q is peaking, not frequency — 0.707 is flat to the corner, below that the…
Series / parallelSeries:
Slew rate & bandwidthFull-power bandwidth: — the highest frequency at which the op-amp can still swing the whole amplitude. Past it the output stops following and simply…