Resistor Divider Calculator
Calculate output voltage for a two-resistor voltage divider.
What this tool calculates
Calculate output voltage for a two-resistor voltage divider. The main inputs on this page are Input voltage (V), R1 - top resistor (Ω), R2 - bottom resistor (Ω). The result is intended to be readable immediately, with the explanation below available when you need to verify the method.
Method and calculation basis
For two resistors, Vout = Vin × R2 ÷ (R1 + R2), assuming the output is not materially loaded.
Worked examples
Known small input
Use a short value whose output you can independently recognise before processing production data.
Byte-sensitive operations
For hashes and encodings, character encoding matters because the algorithm works on bytes, not visual text.
Understanding the result
The output should be read in the units shown beside the result. If you are comparing alternatives, keep all unchanged assumptions identical and alter one input at a time. That makes it easier to see which value is responsible for the difference.
Assumptions, edge cases and accuracy
A syntactically valid transformation is not necessarily safe or semantically correct for a production system. Check the relevant protocol, API, language or device specification.
Sources and methodology
- IETF / relevant standards body — Format and protocol definitions where applicable
- Language or device specification — Implementation-specific syntax and behaviour
Method reviewed for Instant Solvers V10.0 · October 2026. If you find a calculation or explanation that needs correcting, use the site Contact page and include the tool URL and the values you entered.