How many numbers can the average person remember?
About seven, give or take two. That range comes from George Miller’s 1956 paper “The magical number seven, plus or minus two”, one of the most cited papers in psychology. Later research suggests the true limit is closer to four chunks when people can’t group or rehearse, which is why grouping digits helps so much.
| Digits remembered | Rating | What it usually means |
|---|---|---|
| 4 or fewer | Below the usual range | Common when tired or distracted |
| 5–6 | Typical | Within the classic range |
| 7–8 | Above average | The upper half of the classic range |
| 9–10 | Excellent | Usually means you grouped digits |
| 11 or more | Exceptional | Chunking strategies at work |
These bands are a rough guide built around Miller’s range, not norms from a standardized test.
What this test measures
Holding a string of digits in mind uses verbal working memory: the short-term store you use to keep a phone number, a code or a list in your head while you use it. Psychologists Alan Baddeley and Graham Hitch called the part that repeats sounds to itself the “phonological loop”.
Digit span is also one of the subtests in the Wechsler intelligence scales, where it feeds into the working memory index. On its own, though, it is one narrow skill, not a measure of overall intelligence.
How to remember more digits
- Chunk: read 492 817 3 as three groups, like a phone number, not seven separate digits.
- Say it in your head: silent rehearsal keeps the sound of the number alive.
- Find meaning: 1984, 365 or 007 are easier as one item than as three or four digits.
- Use rhythm: a beat (“four-nine, two-eight, one-seven”) makes the order stick.
The student who reached 79 digits
In 1980, psychologists K. Anders Ericsson, William Chase and Steve Faloon published the case of a student, known as S.F., who practiced digit span in hour-long sessions. After more than 200 hours of practice he could recall 79 digits. His trick was turning groups of digits into running times, since he was a keen runner. Tested on letters instead, his span barely moved, which showed that his skill, not his raw capacity, had grown.
Number memory test FAQ
Is remembering 10 digits good?
Yes. Ten digits is above the classic range of five to nine, and usually means you grouped the digits into chunks, which is a skill, not a trick.
Is this the same as a digit span test?
It measures the same thing in a slightly different way. Standard digit span tests, like the one in the Wechsler scales, read digits aloud one per second; here you see the whole number at once, so visual grouping helps a little more.
Can you train your number memory?
Yes, dramatically. In a famous 1980 study, a student practiced for more than 200 hours and went from about seven digits to 79 by inventing ways to chunk them. The gain stayed specific to digits.
Why does it suddenly get hard around seven digits?
That is roughly where working memory runs out of room for separate items. Past that point you need to rehearse the digits or group them, and any distraction knocks something out.
Sources
- Miller, G. A. (1956). The magical number seven, plus or minus two. Psychological Review, 63(2), 81–97.
- Cowan, N. (2001). The magical number 4 in short-term memory. Behavioral and Brain Sciences, 24(1), 87–114.
- Ericsson, K. A., Chase, W. G., & Faloon, S. (1980). Acquisition of a memory skill. Science, 208, 1181–1182.
- Baddeley, A. D., & Hitch, G. (1974). Working memory. Psychology of Learning and Motivation, 8, 47–89.
Memory is one piece of the puzzle
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Take the free IQ testBy the MyIQTest team · Reviewed November 2026