Measured in digits recalled ยท higher is better
Number Memory Test
A number appears. It disappears. Type it back. It gets one digit longer each time.
Before you start
The median on mouse is 8 digits. Run the test and we will place you against it.
Compared against
Typing on a phone keypad adds time between digits, which costs recall. Ranked separately from keyboard entry.
The other device classes
Trackpad
Touchscreen
Curve is a fitted baseline plus 0 first attempts recorded here. The baseline is a curve, not a sample: no part of it is a real person. Baseline is an estimate: centred on the classic seven plus or minus two digit span, nudged up for a self selected audience. No published dataset was found for it. Per-device offsets are extrapolated, not measured. The baseline is dropped once a device class holds 5,000 real first attempts. See the full distribution.
Hold the number
A number appears, then disappears. Type it back. It gets one digit longer every time you get it right, and one mistake ends the run.
Understanding your score
| Band | digits | What it means |
|---|---|---|
| Exceptional | 14 and above | Almost always a memorisation technique. |
| Very good | 11 to 13 | Well above the classic span. |
| Good | 9 to 10 | Above average. |
| Average | 7 to 8 | The classic seven plus or minus two. |
| Below average | 5 to 6 | Common when distracted. |
| Low | 4 and below | Try again in a quiet room before reading anything into it. |
Seven plus or minus two
Digit span is the oldest measurement in cognitive psychology still in regular use. George Miller described the limit as seven plus or minus two in 1956, and the number has held up remarkably well: most adults recall seven to nine digits.
Later work argued the real limit is closer to four chunks, and that the higher digit counts come from grouping. Both are true. You hold about four things, and each thing can be more than one digit if you make it so.
How people get past nine
Chunking. 4 9 2 7 is four items. Forty-nine twenty-seven is one. Anyone scoring above 11 is doing some version of this, usually without describing it that way.
Meaning. Digits that happen to form a year, an area code, or a familiar number cost almost nothing to store. Practised competitors deliberately convert digit groups into images or words.
Rehearsal. Saying the number to yourself keeps it alive in the phonological loop, which is why background conversation hurts this test far more than it hurts the visual memory test.
One deep breath before the number appears is worth more than any of these. Most failures at eight and nine digits are attention failures, not capacity failures.
Why one mistake ends the run
Digit span is defined as the longest sequence you can reproduce correctly, so a partially correct answer is not a shorter success. Allowing retries would measure persistence rather than span.
That does make a single slip expensive. Run it twice and take the better result if you want a number that reflects your typical performance rather than your worst moment.
Where the digits are held
Digits are stored as sounds, not as symbols. Even reading silently, you convert them into inner speech and keep them alive by rehearsing that speech. This is the phonological loop, and it has a duration limit of roughly two seconds of speech rather than a fixed count of items.
That explains an odd finding: people recall more digits in languages where the digit words are shorter. Speakers of languages with brief digit names fit more into the same two seconds. Nothing about their memory differs, only the length of what they are rehearsing.
It also explains why saying anything else while you hold the number destroys it. Counting aloud, or even reading a sentence, occupies the loop and the digits fall out within a second or two.
Questions
- Why do the digits vanish if I speak while holding them?
- Because they are held as inner speech. Speaking occupies the same channel, so the rehearsal stops and the trace decays within a couple of seconds. This is a well-documented effect called articulatory suppression.
- What is a good number memory score?
- Seven to nine digits is normal for adults. Ten or more is above average. Anything past 13 almost always involves a deliberate chunking or memorisation technique.
- Can I improve my digit span?
- Yes, considerably, by learning to chunk. Trained individuals have reached spans in the dozens. What does not change is your underlying capacity, roughly four chunks. You get better at packing more into each chunk.
- Why is this harder with music playing?
- Digits are held in the phonological loop, the part of working memory that handles sound and inner speech. Music with lyrics and background conversation compete for the same system. Instrumental music interferes far less.