Voltage divider calculator
Calculate unloaded output of a two-resistor voltage divider. Your inputs stay in this browser tab.
Your result
A little input. A useful result.
Your result will appear here.How to use voltage divider calculator
Calculate unloaded output of a two-resistor voltage divider. This free tool runs locally after you choose to start.
- Enter your own values, or start with the visible example.
- Adjust input voltage (v), top resistance (ohms), bottom resistance (ohms) as needed.
- Choose the action button. Review the result, then copy text or download a file when available.
- Choose Clear all when finished to remove inputs and results from the interface.
Limits, without the small print.
Use consistent units as labeled. Floating-point results are estimates. Unloaded output; source impedance and load current are excluded.
One job runs at a time. You can cancel it; jobs stop after 30 seconds. Browser and device capabilities affect performance.
Understand the safeguards →What this tool does
Vout = Vin × Rbottom/(Rtop + Rbottom).
Example input
Input voltage (V): 12; Top resistance (ohms): 10000; Bottom resistance (ohms): 5000
Example result
{
"volts": 4
}A couple of useful answers.
Does voltage divider calculator upload my data?
No. This tool processes your input in a browser worker. Your text and files are not sent to an application server. The static host receives page and asset requests; see our privacy explanation.
Is this tool free for work and study?
Yes. No account, paid API, usage subscription or watermark fee is required. You remain responsible for your content rights and checking results. Hosting providers and their free tiers are separate from this open-source software.
What should I check before relying on the result?
Use consistent units as labeled. Floating-point results are estimates. Unloaded output; source impedance and load current are excluded. Review important outputs against the source, especially financial, legal, identity, medical and research calculations.