E-Series Resistor Solver
Finds the standard E-series resistor closest to any target value, and the best two-resistor series or parallel combination when a single part is not close enough. Also solves voltage-divider ratios: give a target Vout/Vin and get the best standard pairs ranked by error.
Read the full guide to this tool
Results
Notes
- E-series values repeat each decade on a logarithmic grid: E24 has 24 values per decade, E96 has 96. The series number also hints at the usual tolerance grade the values are sold in.
- A combination can beat any single value on paper, but two 5% parts still give roughly a 5% result; use 1% parts when the ratio matters.
- Divider pairs keep their ratio when both resistors are scaled by the same power of ten, so pick the decade that suits your current budget and noise needs.
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