Memory2 min read

How to play N-Back

Letters appear one at a time. Press Match when the letter on screen is the same as the one a set number of steps back.

Goal

Catch the matches and leave the rest alone: a round passes at 80% right overall, with at least half the matches caught.

The level sets N: 1-back on Easy (the letter just before), 2-back on Medium and Hard, 3-back on Expert.
Each letter shows for a moment, then the next arrives. Decide on every one.
Press Match, Space or M while a letter is showing to call it a match.
A round is 15 to 20 letters. The results show the whole stream with the matches marked.

In 2-back, the stream B, K, B is a match on the second B: it's the same as the letter two steps before it.

Keys	What it does
`Space`	Match (M works too)

Keep a running list of the last N letters in your head: drop the oldest, add the newest, every time.
From Medium, near-misses repeat one step too early or too late - only exactly N back counts.
On Easy and Medium, a hint shows the last N letters on screen for the rest of the round.

Every correct answer is worth 100 points, scaled by difficulty (Easy ×0.8, Medium ×1, Hard ×1.3, Expert ×1.6).
Answering within 3 seconds adds a 25-point speed bonus.
Each answer in a row adds a 15-point streak bonus, up to 10 in a row.
Using a hint halves the points for that answer and skips the bonuses. Hints are only available on Easy and Medium.
Your score, streak and achievements are saved to your account when the game ends.

Classic

A fixed number of rounds, then a results screen.

Endless

Keep playing until you press Quit.

Time Attack

Fit in as many rounds as you can before the clock runs out.

Survival

Play until you run out of lives or make the game-ending mistake.