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One Quick Try

N-Back Test

Does this letter match the one from N steps ago? Keep the last few in mind and find out.

Type
Memory
Takes
about 2 min
Result in
% accuracy

N-Back

~2 min

  1. Letters appear one at a time, one every 2.5 seconds.
  2. Press Match (or M / Space) when a letter is the same as the one 2 letters before it.
  3. 20 letters are scored, 6 of them matches. Your result is how many you got right.
How far back

Say the last few letters to yourself as they come.

Your result: — % right

How it's measured

Try another challenge

  • Digit Span

    Repeat the digits, forward or backward.~2-4 min

  • Chimp Test

    Remember where the numbers were, in order.~2 min

  • Sequence Memory

    Repeat the order the tiles light up.~1-3 min

  • Verbal Memory

    Seen this word before, or new?~1-3 min

  • Go/No-Go

    React to the circle. Hold back on the square.~1 min

  • Flanker Test

    Which way does the middle arrow point?~1 min

How does the n-back test work?

Letters appear one at a time, each for 0.5 seconds, one every 2.5 seconds. Press Match when the letter on screen is the same as the one N letters before it. In 2-back, for example, the sequence K, R, K has a match on the second K. You choose N: 1, 2, 3. A tick or a cross confirms each press, so you learn the rule as you go.

How is your result calculated?

20 letters are scored, and exactly 6 of them are matches. Every scored letter is a decision: pressing for a match is a hit, letting a non-match pass is a correct rejection. Your result is the share of decisions you got right. Missed matches and false alarms (pressing when it wasn't a match) are shown separately, because they are different mistakes.

What does the n-back test measure?

Working memory: holding a few items in mind and updating them as new ones arrive. Every letter forces you to drop the oldest one you were holding and take in the new one, so the task gets much harder with each step of N. It was introduced by Wayne Kirchner in 1958 and is now one of the most used tasks in memory research and brain imaging.

Does n-back training make you smarter?

Probably not. A 2008 study suggested that practising a dual n-back task raised scores on reasoning tests, which made n-back training popular. Later work did not hold that up: a 2016 review of 87 publications by Monica Melby-Lervåg, Thomas Redick and Charles Hulme found that working memory training improves the trained tasks and similar ones, but not intelligence or other distant skills. Practise it because it is a good challenge, not as brain training.

For other working memory tests, try the Digit Span Test or the Chimp Test.

Questions

What is a good n-back score?
There is no single standard: scores depend on N, the letters, the speed and the share of matches, which differ between versions. Compare your accuracy at the same N over several runs; each extra step of N makes the task markedly harder.
What is the difference between 2-back and dual n-back?
In plain 2-back you track one stream, letters here. Dual n-back tracks two at once, usually positions on a grid and spoken letters, with a separate button for each.
Why does a press only count once per letter?
So pressing repeatedly can't score extra hits. Each letter is one decision: match or not.
Should I press for the first letters?
No. The first N letters have nothing N back to match, so they aren't scored.