Increasing digit span
Study a random digit string, wait for it to disappear, and type it back. A correct answer advances to a longer string up to 20 digits; settings control exposure time, strict comparison, and visual spacing.
Hold a displayed digit string, then enter it after it disappears.
Max span
0
Current length
5
Accuracy
0%
Attempts
0
The page tests recall of one generated digit string at a time. Visual grouping can change encoding, while strict mode controls whether formatting differences are accepted.
The longest completed length belongs to this task and setup. It is not an IQ score, clinical digit-span norm, or proof of general memory capacity.
A string begins at the selected length and stays visible for the configured duration. After it is hidden, submit the digits from left to right. Correct recall increases length; an incorrect answer records the reached span.
Spaces are a display aid. Changing spacing or strict matching changes the task context, so history comparisons should keep them fixed.
Longer exposure gives more encoding time, and grouped digits may support chunking. Compare only records with the same starting length, exposure, spacing, and validation rule.
The page lacks controlled administration, age norms, and forward/backward clinical procedures. Keyboard familiarity and display choices are part of the result.
The recent result is saved locally in this browser and can be removed by clearing site data. No digit answers are sent to an account.
These questions stay tied to the visible content on this page.
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