Online memory trainer

N-back 3: compare the square with the one from three steps back

Also known as: 3-back, 3-back test, N-back with N = 3

Squares on a 3×3 grid light up one at a time. Press “Match” if the same square lit up three steps back. The whole game runs at N = 3: three blocks, about three minutes. You can play 10 minutes a day without signing up.

Go to the game ↓

≈3 minutesthree blocks
N = 3level stays fixed
No sign-up10 minutes a day
Progress30-day chart

What it trains

Why train with N-back 3

This is the heavy version of the working memory task: you hold the last three squares in mind, and they shift at every step. You can’t answer by eye; you have to keep remembering what came three steps back.

The level is locked at N = 3 in all three blocks, so you can compare scores from different games directly. Once you sign up, every game is saved and you can see a chart in your account.

You get through N-back 2 almost error-freeTime to add one more step
You love tasks at your limitIt’s easy to slip up here even in the first block
You lose the order of eventsYou remember what happened, but not when
You want honest progress trackingThe same level in every game

Working memory

Keep the last three positions in mind and update them at every step.

Focus

Three minutes at a set pace with no pauses inside a block.

Inhibition

Don’t press if a square matches the one from one or two steps back.

Order

Remember not only the places but also the order in which they lit up.

Rules

How to play

Start
Press “Start”. The top of the screen says: press if the square is the same as 3 steps back.
Watch
Every 2.5 seconds one square on the 3×3 grid lights up; the glow lasts one second.
Match
If the square is the same as three steps back, press “Match” or the space bar. If it isn’t, don’t press anything.
Points
Each match you catch earns 30 points. A wrong press costs 5 points; a miss earns nothing.
Blocks
A game has three blocks of 23 steps. The level doesn’t change between blocks: N = 3 all game.

Play online

N-back 3 online

Press “Start”, then hit “Match” or the space bar whenever a square repeats the one from three steps back.

N-back 3

Cells light up one by one. Tap “Match” if the cell is the same as three steps back. The level stays the same: the whole game is played with N = 3.

Free play left today without signing up: 10 min

Method

What the exercise is based on

N-back is a classic cognitive psychology task for studying working memory. The bigger N is, the more positions you have to hold and update at once, so N = 3 is noticeably harder than N = 2. Our site uses the single version with positions on a 3×3 grid.

If three steps feel too hard for now, go back to N-back 2 or the regular N-back, where the level adapts to your accuracy.

N=1Regular N-backThe game starts at N = 1, then the level changes on its own.

N=2N-back 2The last two squares in mind, 20 points per match.

N=3This versionAll three blocks at N = 3, 30 points per match.

Who it’s for

Which ages

Adults

For those who already handle N-back 2 with confidence. One of the hardest memory exercises on the site.

Kids

Not part of the “Kids” collection: the pace is too fast and the rule too complex. Corsi Blocks or Remember the Number are a better fit for kids.

60+

Not part of the “60+” collection: the pace is fixed, and the rule means holding three steps in mind. Remember the Number is a gentler place to start.

Questions

Frequently asked questions

How is N-back 3 different from N-back 2?

You compare with the square from three steps back instead of two. You hold one more position in mind, and a match earns 30 points instead of 20.

Why is it so hard?

Every new square shifts the whole row, and you have to remember the order of the last three. It’s normal to catch only a few matches in your first games: compare yourself with yourself.

What counts as a mistake?

Pressing when the square doesn’t match the one from three steps back. It costs 5 points. A missed match doesn’t cost anything.

Can I play with the keyboard?

Yes, the space bar works as the “Match” button. On a phone, tap the button below the grid.

Do I need to sign up?

No, you can play 10 minutes a day right away. A free account lets you keep playing, save your results, track your progress and unlock the daily workout.

Save your results and track your progress

Free sign-up: round history, a chart by skill and a daily workout of 5 exercises. No credit card needed.

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N-back 3: compare the square with the one from three steps back