How does the number memory game work?

Press Show number when you are ready. A number appears for the selected display time and is removed before the answer field opens. Type the full sequence of digits or skip the trial. After submitting, review exact-match feedback and the digit positions you recalled correctly.

Do leading zeroes count?

Yes. Numbers are generated and checked as digit strings. If the sequence is 0123, entering 123 is not an exact match. Missing or extra digits prevent an exact match, even if some positions are correct. Spaces and nondigit input are rejected rather than silently removed.

What can I configure in practice?

Choose 2–30 digits, a display time of 0.5–30 seconds in half-second steps, and 1–50 trials. Enter a whole seed from 0 to 4,294,967,295 to reproduce a sequence, or leave it blank for a new seed. Settings apply only when you start a practice run.

What settings does a shared challenge use?

Every shareable challenge has ten six-digit numbers, each shown for three seconds. The seed fixes the sequence and order. A completed visible run with at least one entered answer can share its exact-match count out of ten. Known replays, interrupted runs and fully skipped runs stay practice. Scores are self-reported, not verified rankings. Replay detection uses this page and up to 100 exposed seeds saved on this device when storage works; clearing or blocking storage limits recognition across reloads.

What happens if I switch tabs or end a run?

Moving the page into the background during a display hides the number immediately and opens the answer phase. Leaving an active run makes it interrupted practice, so it cannot create an independent scored challenge. Browser suspension can still affect timing. End run preserves submitted trials but does not score an unfinished one. Restart same run returns to the first number as practice and clears prior timers and pending output ownership.

What do the chart and review show?

The session chart shows correct digit positions for every submitted trial and distinguishes exact matches. The review and TXT download include expected numbers, entered answers and per-trial results. Those details stay in the browser unless you download them; they are not included in challenge links or analytics.

Is practice history saved?

The page retains up to 20 completed practice summaries. Optional device history saves dates, digit lengths, display times, trial counts and aggregate scores in local storage, without answers or challenge results. Restoration is read-only. A new summary merges into the latest usable history; unsupported, inconsistent or unreadable records are kept. Turning saving off or choosing Forget saved practice history explicitly removes that record. Storage failures do not prevent playing. Replay seed records are separate and retained.

Does this measure IQ or cognitive health?

No. It is a recreational recall game. The result depends on practice, attention, chosen settings and browser timing. It provides no IQ estimate, diagnosis, population norm or cognitive-health conclusion.

What happens if copying or downloading fails?

The complete current challenge text and submitted-trial review remain selectable. A failed TXT or PNG preparation or native clipboard/share request opens the corresponding selectable text. Pending output loses ownership after another output request, editing, restart, hiding or navigation. Downloads and sharing report browser handoffs; the page cannot confirm a file was saved or a challenge was delivered.

Number Recall Game

Memorize a number before it disappears, then type it from memory. Adjust digit length and display time for practice, inspect matching positions, and share a ten-trial challenge that reproduces the same numbers for a recipient.

Practice settings

Digits per numberDisplay secondsTrial countSeed (optional)

2–30 digits, 0.5–30 seconds in half-second steps, 1–50 trials. Leading zeroes count. Settings take effect when you start a new practice run; they do not change the active run.

Practice session history

Save practice history on this device

Up to 20 completed practice summaries. Challenge runs and answers are not saved. Without this option, history lasts only until reload. Turning it off explicitly forgets saved practice history. A failed write or unusable record is kept; Forget saved practice history also removes an unusable record. Replay records contain only the last 100 exposed seeds, are separate, and stay on this device when storage works.

No completed practice sessions yet.

A recreational recall game, not an IQ test, diagnosis, population comparison or cognitive-health assessment. Display timing depends on the browser; shared scores are self-reported. Game processing stays in your browser. Challenge events include only the tool and configuration seed when measurement is allowed, never entered answers. Replay detection uses this page and, when available, the last 100 exposed seeds saved on this device; cleared or unavailable storage limits detection across reloads.

Common questions

How does the number memory game work?: Press Show number when you are ready. A number appears for the selected display time and is removed before the answer field opens. Type the full sequence of digits or skip the trial. After submitting, review exact-match feedback and the digit positions you recalled correctly.
Do leading zeroes count?: Yes. Numbers are generated and checked as digit strings. If the sequence is 0123, entering 123 is not an exact match. Missing or extra digits prevent an exact match, even if some positions are correct. Spaces and nondigit input are rejected rather than silently removed.
What can I configure in practice?: Choose 2–30 digits, a display time of 0.5–30 seconds in half-second steps, and 1–50 trials. Enter a whole seed from 0 to 4,294,967,295 to reproduce a sequence, or leave it blank for a new seed. Settings apply only when you start a practice run.
What settings does a shared challenge use?: Every shareable challenge has ten six-digit numbers, each shown for three seconds. The seed fixes the sequence and order. A completed visible run with at least one entered answer can share its exact-match count out of ten. Known replays, interrupted runs and fully skipped runs stay practice. Scores are self-reported, not verified rankings. Replay detection uses this page and up to 100 exposed seeds saved on this device when storage works; clearing or blocking storage limits recognition across reloads.
What happens if I switch tabs or end a run?: Moving the page into the background during a display hides the number immediately and opens the answer phase. Leaving an active run makes it interrupted practice, so it cannot create an independent scored challenge. Browser suspension can still affect timing. End run preserves submitted trials but does not score an unfinished one. Restart same run returns to the first number as practice and clears prior timers and pending output ownership.
What do the chart and review show?: The session chart shows correct digit positions for every submitted trial and distinguishes exact matches. The review and TXT download include expected numbers, entered answers and per-trial results. Those details stay in the browser unless you download them; they are not included in challenge links or analytics.
Is practice history saved?: The page retains up to 20 completed practice summaries. Optional device history saves dates, digit lengths, display times, trial counts and aggregate scores in local storage, without answers or challenge results. Restoration is read-only. A new summary merges into the latest usable history; unsupported, inconsistent or unreadable records are kept. Turning saving off or choosing Forget saved practice history explicitly removes that record. Storage failures do not prevent playing. Replay seed records are separate and retained.
Does this measure IQ or cognitive health?: No. It is a recreational recall game. The result depends on practice, attention, chosen settings and browser timing. It provides no IQ estimate, diagnosis, population norm or cognitive-health conclusion.
What happens if copying or downloading fails?: The complete current challenge text and submitted-trial review remain selectable. A failed TXT or PNG preparation or native clipboard/share request opens the corresponding selectable text. Pending output loses ownership after another output request, editing, restart, hiding or navigation. Downloads and sharing report browser handoffs; the page cannot confirm a file was saved or a challenge was delivered.

A recreational recall game, not an IQ test, diagnosis, population comparison or cognitive-health assessment. Display timing depends on the browser; shared scores are self-reported.