How it works
Fill in the 4 fields above and Odds Ratio Calculator calculates the result instantly, recalculating as you change any value. It applies the formula OR = (a·d) / (b·c). The math runs locally in your browser — nothing is sent to a server.
Formula
OR = (a·d) / (b·c)Examples
- Exposed cases (a) 30, Exposed controls (b) 70, Unexposed cases (c) 10 → Odds ratio: 3.86
Frequently asked questions
How do I use the Odds Ratio Calculator?
Enter your values in the 4 input fields and the result is calculated automatically as you type. Change any value to see the numbers update instantly.
What formula does the Odds Ratio Calculator use?
It uses OR = (a·d) / (b·c). The calculation is performed in your browser using standard, well-established math for accurate results.
Is my data private?
Yes. The Odds Ratio Calculator runs entirely in your browser. Nothing you enter is uploaded, saved to a server, or shared — it never leaves your device.
Is the Odds Ratio Calculator free?
Yes, it is completely free with no sign-up, no limits and no watermarks. Like every tool on statistics and the rest of the platform, you can use it as often as you like.
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