Standard Deviation
Mean, variance, SD.
▶ Open Standard DeviationStandard Deviation is a free online math & science tool that helps you mean, variance, SD. Everything happens right in your browser, so it's fast, completely private, and free — no account, no installs, and no watermarks.
What is Standard Deviation?
Standard Deviation is built for anyone who needs to mean, variance, SD without downloading software or signing up. Students, teachers and engineers need dependable answers to common calculations without pulling out a graphing calculator. Standard Deviation solves that in one click, right in your browser — and because the work happens on your own device, it's both instant and private.
How to use Standard Deviation
- Click “Open Standard Deviation” to launch the tool.
- Enter your numbers in the fields.
- Read the result — it updates as you type.
- Tweak the values to compare different scenarios.
Common uses
- Verify a formula result while studying.
- Crunch statistics for a report or experiment.
- Solve an equation you'd otherwise do by hand.
- Check homework answers step by step.
Why use Somar's All Free Tools?
- Free forever — every feature, no hidden paywall or watermark.
- Private by design — processing happens on your device, not our servers.
- Instant — no queues, no waiting, no upload time.
- Works everywhere — desktop, tablet and mobile, nothing to install.
- No signup — just open it and go.
Frequently asked questions
Is Standard Deviation free to use?
Standard Deviation is completely free. There are no limits, no watermarks on your results, and no sign-up required.
Is my data private and safe?
Yes. Everything runs locally in your browser, so the data you enter never leaves your device.
Do I need to install anything or create an account?
No. Standard Deviation works instantly in any modern browser on desktop, tablet or mobile — nothing to download and no account needed.
How accurate are the results?
Standard Deviation uses standard formulas and recalculates instantly. Results are estimates for general guidance; see our Disclaimer for health and finance tools.