Non-Inverting Amplifier Calculator

Summary

Enter the input voltage, R1, and Rf to instantly calculate the closed-loop gain and output voltage of an op-amp non-inverting amplifier.

How it works

1. Select the calculation mode: compute gain from resistors, or find Rf for a target gain.
2. Enter the input voltage (Vin) in volts.
3. Enter the R1 (ground resistor) value in ohms, kilohms, or megaohms.
4. Enter the feedback resistor Rf (or target gain in solve mode).
5. The calculator applies Gain = 1 + (Rf / R1) to find the closed-loop gain.
6. Output voltage is computed as Vout = Gain x Vin, and results update instantly.

Use cases

• Design buffer and amplifier stages that preserve signal polarity.
• Size Rf and R1 for a specific gain target in a sensor interface circuit.
• Verify resistor selections for audio preamplifier stages.
• Quickly check gain and output swing before building a prototype.
• Teach op-amp non-inverting amplifier theory with live feedback.
• Convert low-level sensor outputs to ADC input ranges without phase inversion.
• Design voltage followers by setting Rf to 0 and R1 to infinity (unity gain).
• Estimate output voltage headroom against supply rails.

Frequently Asked Questions