LM317 Output Voltage Calculator Enter any two values among R1, R2, and Output Voltage (Vout). Leave the third one blank to calculate it. Resistor R1: ΩkΩMΩ Resistor R2: ΩkΩMΩ Output Voltage (V): Calculate Clear Note: The LM317 output voltage is calculated using: Vout = 1.25 × (1 + R2 / R1). Ignores Iadj for simplicity.