Standard Deviation (SD)

IQ Test › IQ Glossary & Terms › Standard Deviation (SD)
Standard deviation measures how spread out scores are around the mean. On the Wechsler scale the IQ standard deviation is 15, so most people fall between 85 and 115.

IQ Glossary & Terms

📅 Last updated: 2026-06-18 · ✔ Reviewed by the All-Lifes editorial team · About · Methodology
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