Math

Standard Deviation Calculator

Built by Kevin Glover · @gloverbuilds · Verified formula

Calculate standard deviation, variance, and mean from a data set. Population and sample. Free calculator.

📅 Updated April 2026 ✅ Formula verified 📖 4 min read 🆓 Free · No sign-up

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How to Use This Calculator
Tips for Best Results

Streuung

Die Standardabweichung misst wie weit Daten vom Durchschnitt abweichen. Niedrig = eng beieinander. Hoch = breit gestreut. DAX historische Volatilitaet: ~20-25%/Jahr.

68-95-99,7-Regel

68% innerhalb ±1 SD. 95% innerhalb ±2. 99,7% innerhalb ±3.

⚡ CalcWolf Insight

In investing, standard deviation IS risk. The S&P 500 has a historical SD of 15-16%, meaning a 30% swing in either direction is a once-per-generation event — but it does happen.

Frequently asked questions

Was ist Standardabweichung?▾

Wie weit Daten vom Mittelwert abweichen. SD 5 bei Mittel 100: Grossteil zwischen 95-105.

Population oder Stichprobe?▾

Population: alle Daten. Stichprobe: Teilmenge (durch n-1 teilen).

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Kevin Glover · @gloverbuilds

Founder, CalcWolf · GLVTS · Blickr

All formulas sourced from primary references — IRS publications, peer-reviewed research, and official standards. Results are tested against independent reference calculators before publishing. Rates and brackets updated when official sources change. Editorial policy →