Short-term memory test online

The classic short-term memory check (digit span): memorise a string of digits and type it back — each step makes the string longer. The test shows your memory span in digits — right in the browser, free and with no sign-up.

Memorise a string of digits — they appear one at a time — then type it back from memory. Correct — the string gets one digit longer; you have two tries per length. The test ends when both tries fail: your span is the longest string without an error.

7 ± 2

Short-term memory span norms

Adult reference points for the classic digit span test (the longest string reproduced without an error). The famous “seven plus or minus two” is exactly about this.

  • 9 or moreExcellent — span above most adults
  • 8Good result — above typical
  • 6–7Typical range for adults
  • 5Below typical — possibly fatigue or lost focus
  • 4 or lessNotably below the reference — mind your sleep, stress and deficiencies

What short-term memory is

Short-term memory is the brain’s “desktop”: for a few seconds it holds whatever you are working with right now — a phone number, an address, a name you just heard. Its capacity is limited: George Miller’s classic estimate is “seven plus or minus two” items; modern research points to about four larger chunks.

The digit span test is the standard way to measure this capacity: it is part of well-known intelligence and memory batteries. The online version gives you a practice reference — how long a string you can hold without an error.

How to take the test

A few rules for an honest result:

  • take it in silence — any distraction “wipes” the string from short-term memory;
  • don’t write the digits down or photograph them — the point is holding them in your head;
  • use chunking: “49-17-53” is easier than “4-9-1-7-5-3” — that is a fair technique, not cheating;
  • repeat the test at the same time of day to see real progress.

What affects memory

Short-term memory is very sensitive to your state: sleep deprivation, stress and anxiety, multitasking and plain fatigue lower the result noticeably. This is reversible — after rest the span comes back.

If memory keeps failing — words, names, why you walked into the room — the cause can be physical: vitamin B12 deficiency, low ferritin, an underactive thyroid, chronic sleep debt. These show up in ordinary labs and are worth checking first.

Frequently asked questions

  • Most adults reliably reproduce a string of 6–7 digits. Eight is a good result, nine or more is excellent. Five or fewer usually means fatigue or distraction rather than “bad memory” — retry when rested.

  • The raw “desktop” size trains poorly, but how efficiently you use it trains very well: chunking, associations and mnemonics let you hold noticeably more. Regular practice improves the score mostly through strategies.

  • This online test does not diagnose dementia and is not meant to. A one-off low score is almost always fatigue, stress or sleep debt. What warrants attention is a steady everyday decline that family notices — that is a reason for an in-person neurological assessment.

  • Short-term memory “lives” in the prefrontal cortex — the brain area most sensitive to sleep loss and cortisol. One sleepless night impairs it more than it feels. Sleep is the main “vitamin” for memory.

  • Persistent decline in memory and focus occurs with B12 and iron (ferritin) deficiency, hypothyroidism, depression and sleep apnea. Start with labs — upload them to our service, AI explains every value and tells you what to discuss with a doctor.

Memory doesn’t fail “just because”

B12 and iron deficiency, an underactive thyroid and poor sleep are frequent physical causes of “bad memory”. Upload your labs — AI explains every value and tells you what to check.

Decode my labs

The memory test on this page is a trainer and a reference point, not medical diagnostics (and not a dementia test). If memory decline is noticeable in daily life and lasts, discuss it with a doctor.