What an IQ of 84 means

An IQ of 84 is higher than about 14.3% of people: roughly 1 in 7 score 84 or lower. It is in the low average range, 1.07 standard deviations below the average of 100.

Figure 1. Where an IQ of 84 sits on the bell curve

The amber band is the likely range on a retake of our test, 9 points either side. The curve is the normal distribution with a mean of 100 and a standard deviation of 15.

Is an IQ of 84 good?

It is a little below the middle, in the low average range: higher than about 14.3% of people. On one short test a tired or rushed sitting can easily move a score this much.

What percentile is an IQ of 84?

An IQ of 84 is at the 14th percentile: it is higher than 14.3% of people on a scale with a mean of 100 and a standard deviation of 15.

Tests that use a different standard deviation give the same rarity a different number: about 83 on a 16-point scale such as older Stanford-Binet editions, and about 74 on the 24-point Cattell scale.

How rare is an IQ of 84?

About 1 in 7 people score 84 or lower. In a group of 1,000 people, about 143 would be expected to score that low or lower.

How much could a retake change it?

No test gives the same score twice. The likely range is where about 90 in 100 retakes would land, and its width depends on how reliable the test is.1

Table 1. The likely range for a score of 84
TestMargin of errorLikely range
Our test (reliability 0.87)±975 to 93
A test with reliability 0.90±876 to 92
A test with reliability 0.95±678 to 90

The margin is 1.645 standard errors of measurement, which covers about 90% of retakes.

What an IQ of 84 does not tell you

A score describes how someone did on one set of reasoning tasks on one day. It does not measure what a person knows, how hard they work or what they will achieve.

An online test is for interest. For a score that counts for school, work or health, a psychologist can give a full assessment in person.

Nearby scores

Sources

  1. American Educational Research Association, American Psychological Association and National Council on Measurement in Education (2014). Standards for Educational and Psychological Testing, chapter 2: Reliability/Precision and Errors of Measurement. www.testingstandards.net/open-access-files.html

First published 13 November 2026.