EveryMemoryWhat Is the Average IQ?
The average IQ is 100 by definition, with about two-thirds of people scoring between 85 and 115. Here's what those ranges mean - and why the number is less dramatic than it sounds.
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⚡ Quick answer
The average IQ is 100 by definition, because the test is scaled that way. About 68% of people score between 85 and 115, and roughly 95% fall between 70 and 130. Scores anywhere in the 85–115 band are completely typical - that's most of the population.
Key takeaways
- The average IQ is 100 by design, not by discovery - the scale is anchored there.
- About 68% of people score 85-115; roughly 95% fall between 70 and 130.
- Small point gaps are often within test noise (sleep, stress, format familiarity).
- Being near 100 says nothing about creativity, judgement, or achievement.
Ask what the average IQ is and the answer is suspiciously round: it's 100. That isn't a coincidence or a discovery - it's a design choice. IQ tests are deliberately scaled so that the typical score in the population comes out at 100.
Which means the more interesting questions are about the spread. How far above or below 100 is unusual? What does a 115 or an 85 actually mean? And why do small differences get treated as huge when they're often within the noise of a single test sitting? This guide answers all three plainly.
Why the average is exactly 100
IQ uses a standardized scale with a mean of 100 and a standard deviation of 15. The mean is the centre, and the standard deviation describes how spread out scores are. Because the test is calibrated against a representative sample, the average is set to 100 by construction - not measured and found to be 100 by luck.
This is why you can't really have a population whose "average IQ rose to 110" on the same scale - the average is re-anchored to 100 when tests are restandardized. The number tells you where you sit relative to everyone else, not an absolute quantity of brainpower.
The ranges, in plain terms
Here's roughly how scores distribute across the population. These bands are descriptive labels for positions on the curve, not judgements about people.
| IQ range | Roughly where it sits |
|---|---|
| Below 70 | About 2% of people; well below the typical band |
| 70–84 | Below average |
| 85–115 | The average band - about 68% of people |
| 116–130 | Above average |
| Above 130 | Top ~2%; often the "gifted" cutoff |
Notice how wide the middle band is. A score of 90 and a score of 110 sit on opposite sides of 100, yet both are squarely normal. Most apparent "differences" between ordinary people are inside this band.
Why small gaps mean less than they seem
A single IQ test has measurement error. The same person can score several points apart on different days depending on sleep, stress, mood, and how familiar the format feels. So a five-point difference between two people, or between two of your own sittings, is often within the margin of noise.
Treat IQ ranges as broad neighbourhoods, not precise addresses. If you've seen a number from an online quiz, read are online IQ tests accurate before you take it to heart - most aren't standardized at all.
What the average doesn't tell you
Being near 100 says nothing about your creativity, your judgement, your emotional skill, or how much you'll achieve. Plenty of highly effective people sit right in the middle of the distribution, and a high score guarantees none of those qualities.
If you're curious whether you can move your own number, the honest answer is nuanced - we cover it in can you increase your IQ. The short version: you can get better at tests, but raising general intelligence durably is much harder.
⚠ When to talk to a professional
This is general educational information, not medical or psychological advice. IQ ranges describe statistical positions, not a person's worth or potential, and no article can diagnose anything. Speak with a professional about any genuine concern.
