Which level should I start with?

With 1-back. Once accuracy is stably above 90%, move to 2-back — and don’t be surprised by a sharp drop: the difficulty jump between levels is huge by design.

What accuracy is normal on 2-back?

The training zone is 65–79%. Above 80% means confident command of the level, above 90% — time to level up. Below 50% is an honest signal to drop to 1-back and strengthen the base.

Does N-back really raise intelligence?

There is no reliable evidence of transfer to general intelligence — large meta-analyses do not confirm it. N-back improves working memory and similar tasks. That is valuable in itself, but “IQ boost” promises should not be trusted.

Why do I sometimes do well and sometimes completely fall apart?

Working memory is extremely sensitive to your state: sleep loss, stress and even a heavy lunch visibly drop accuracy. Day-to-day swings are normal. Watch the trend over a couple of weeks, not single sessions.

My results keep declining — what should I check?

If working memory has sagged for a while along with focus, check sleep, B12, ferritin and TSH — physical causes give exactly this picture. Upload your labs to our service — AI explains every value.

N-back — working memory trainer

The classic working memory workout: a square appears in different positions — mark when the position matches the one N steps back. Levels from 1-back to 3-back, accuracy in percent. Free, no sign-up.

Level

A square appears in the cells of the board. Press “Match!” when the position is THE SAME as N steps back (Space on the keyboard). There are several matches per round; silence catches none, and random presses drown in false alarms. Starting with 1-back is best.

Accuracy norms for 2-back

Adult reference points at the 2-back level (accuracy = correct responses counting misses and false alarms). Starting at 1-back is perfectly normal — 2-back is hard for almost everyone at first.

90% and aboveExcellent — level mastered, time for 3-back
80–89%Good result — confident command of the level
65–79%Typical range — the training zone
50–64%Hard for now — that is normal, keep practising this level
under 50%Drop to 1-back and strengthen the base

What N-back is

The N-back task was devised by psychologist Wayne Kirchner in 1958, and it has been the gold standard of working memory load in brain research ever since. The essence: stimuli stream past, and at every step you compare the current one with the one N steps back — continuously holding and updating a “sliding window” in your head.

That continuous updating is what makes N-back so demanding: you cannot memorise once and relax — memory runs like a conveyor, as in live conversation, simultaneous interpreting or driving in dense traffic.

How to train

N-back has a steep difficulty curve:

start with 1-back and reach a stable 90%+ before moving up;
2-back feels hard for nearly everyone at first — that is normal, not “bad memory”;
train in short 5–10 minute sessions: attention quality beats duration;
don’t chase levels: a stable 80% on 2-back is worth more than a random 55% on 3-back.

An honest word about “IQ boosting”

There is a lot of marketing noise around N-back: after a famous 2008 study, the trainer was credited with raising general intelligence. Later large-scale checks were more modest: N-back reliably improves working memory itself and closely related tasks, but transfer to “intelligence in general” is not scientifically confirmed.

We say it as it is: this is excellent training of a specific skill — holding and updating information under load. That skill genuinely matters at work and in study, and you will feel it grow. Any promise of “+20 IQ” is advertising, not science.

Frequently asked questions

With 1-back. Once accuracy is stably above 90%, move to 2-back — and don’t be surprised by a sharp drop: the difficulty jump between levels is huge by design.
The training zone is 65–79%. Above 80% means confident command of the level, above 90% — time to level up. Below 50% is an honest signal to drop to 1-back and strengthen the base.
There is no reliable evidence of transfer to general intelligence — large meta-analyses do not confirm it. N-back improves working memory and similar tasks. That is valuable in itself, but “IQ boost” promises should not be trusted.
Working memory is extremely sensitive to your state: sleep loss, stress and even a heavy lunch visibly drop accuracy. Day-to-day swings are normal. Watch the trend over a couple of weeks, not single sessions.
If working memory has sagged for a while along with focus, check sleep, B12, ferritin and TSH — physical causes give exactly this picture. Upload your labs to our service — AI explains every value.

Working memory doesn’t crumble “just because”

Poor sleep, stress, B12 and iron deficiency hit working memory first. Upload your labs — AI explains every value and tells you what to check.

Decode my labs

N-back on this page is a trainer and a reference point, not medical diagnostics and not an “intelligence booster”. If memory decline worries you for a long time, discuss it with a doctor.