A Brief Hobbyist Primer on Effects Pedal Circuits Fixed Resistors - in collaboration with Drunk Beaver's Vitalii Bobrov
External
Parallel Resistor Calculator
Inputs
Solve for R1
Solve for R2
Solve for
Solve for: Calculated for you
Result
Standard values
Enter R1 and R2 to see the total
Schematic
Formula
Total resistance equals R1 times R2 divided by R1 plus R2
Enter R1 and R2 to see the total
About this calculator
Calculate the total resistance of two parallel resistors or determine the required resistor to hit your target value. Designed for the pedal bench with instant E24 and E96 standard value snapping.
Frequently asked questions
How do you calculate parallel resistance?
For two resistors in parallel, total resistance is calculated using the product-over-sum formula: R_total = (R1 * R2) / (R1 + R2). The combined resistance is always lower than the smallest individual resistor.
How do I find a missing resistor for a target parallel resistance?
To solve for a missing resistor R2 given R1 and your target total, rearrange the equation: R2 = (R1 * R_total) / (R1 - R_total). Note that your target total must be strictly smaller than R1.
Why does parallel resistance decrease total resistance?
Connecting resistors in parallel provides multiple independent paths for electric current to flow, increasing total conductance and reducing the overall resistance of the circuit.
What standard resistor series should I use for guitar pedals?
Most guitar pedal circuits and DIY workbench component kits use the E24 series (5% tolerance) or E96 series (1% metal film resistors) for precise tone shaping and bias stability.
Related articles
