N-Back Test: The Letter Matching Game
In this n-back test, letters appear one at a time. Press Match when a letter is the same as the one a set number of steps back. You warm up with the 1-back, then play the 2-back for your score.
- Letters appear one at a time.
- Practice: press Match when a letter is the same as the one just before it (1-back). 12 steps.
- Scored round: press Match when a letter is the same as the one two steps back (2-back). 26 steps.
Keys: Space, Enter or M for Match
Say the last two letters to yourself as you go. Letters change at a steady pace; there is no need to rush.
How does the n-back test work?
The “n” is how far back you compare. In the 1-back, you press Match when a letter repeats the one just before it. In the 2-back, you compare each letter with the one two steps earlier.
The practice round has 12 steps of 1-back and tells you when you miss a match. The scored round has 26 steps of 2-back. Letters come at a steady pace, so you never need to rush.
Why is the 2-back so much harder?
In the 1-back you hold one letter. In the 2-back you hold two, and they keep sliding: each new letter pushes the oldest one out. You have to keep the order straight while you compare.
That is why the n-back is a common lab task for working memory, the kind of memory that keeps a few things in mind while you use them. It first appeared in a study of memory for fast-changing information. Brain imaging studies have used it widely since.
What does my score mean?
Your score is the share of steps you handled right in the 2-back round. A right step is a match you caught or a non-match you left alone. The first two letters cannot match, so they are not counted.
The result also shows four raw numbers. Hits are matches you caught. Misses are matches you let pass. False alarms are presses on letters that did not match. Right non-matches are letters you correctly let go. Pressing on everything would catch every match but add many false alarms, so both kinds of mistake count.
Does the n-back measure working memory well?
It is less precise than it looks. One study compared it with other memory tasks. It found the n-back was not a good measure of differences between people. One reason was that scores were not very stable. The same study found the n-back did relate to reasoning ability.
So treat your score as a game score. Compare it only with your own earlier rounds.
Can dual n-back training raise IQ?
The evidence does not support that. A large review of brain-training studies found that people improve at the task they practice. Gains rarely spread to other skills or daily life. Our brain games page covers this in more detail.
FAQ
What happens if I leave the page?
The round starts again. A stream of letters cannot be picked up in the middle, because you would have lost the last two letters.
What else can I try?
The reverse digits game also asks you to hold and work on items at once. Number memory is a simpler span task. Sequence memory does the same with positions.
For reasoning, try our free IQ test. Our guide on how accurate IQ tests are explains why a game score is different. The test score itself is explained on our methodology page. The cookie policy lists what the games save on your device.