About Sample Size Calculator
Estimate survey or conversion test sample size from baseline rate, minimum detectable effect, confidence, and power. It runs entirely in your browser using client-side processing — your data never leaves your device. No signup, no ads, no watermarks.
Whether on desktop, tablet, or mobile, Sample Size Calculator works instantly with real-time results.
Key Features
Estimate survey or conversion test sample size from baseline rate, minimum detectable effect, confidence, and power.
100% client-side processing — your data stays in your browser.
No signup, no ads, no watermarks — completely free.
How to Use Sample Size Calculator
1
Enter your baseline conversion %
2
Enter your minimum detectable lift %
3
Enter your confidence
4
Enter your power
Why Use This Tool
Works Everywhere
Fully responsive on desktop, tablet, and mobile — no app installation needed.
No Usage Limits
Use as many times as you need. No daily caps, throttling, or forced waits.
Frequently Asked Questions
What is Sample Size Calculator?
Sample Size Calculator is a free online tool from ToolsJungle that runs entirely in your browser. No signup required, no data uploaded.
Is Sample Size Calculator really free?
Yes — 100% free with no hidden costs, premium versions, or usage limits. ToolsJungle is committed to free tools for everyone.
Is my data safe?
Absolutely. All processing is client-side — your data stays in your browser and is never uploaded to any server.
Do I need an account?
No account, email, or registration needed. Open the tool and start using it immediately.
Use Sample Size Calculator Now — Free
No signup · No ads · Instant results · 100% private