OPERATION EVIDENCE
Baseline: buildingWhere time actually goes
Complete a session to see per-operation accuracy and correct-response latency.
MENTAL MATH · GAME-FIRST FLUENCY LAB
Mental Math speed, accuracy and repeatability
Pick a session and start solving. Standard 120 stays fixed for like-for-like practice; custom drills, Daily and Weak Facts stay separate so one score never pretends to measure everything.
Session0 / 10
8 × 7
Quick 10 · Standard · Mixed
Solve the problem. Exact correct answers can auto-submit.
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SESSION COMPLETE
STANDARD 120
0/5 cleanClean 5-run repeatability
Runs0/5
Median rate—
Best—
Range—
CV—
Only uninterrupted Standard 120 runs enter this pack. It describes your own repeatability; it is not a percentile, IQ score, certification or employer cutoff.
Personal coach
Finish a run to identify your slowest or least accurate operation using only local session data.
Recent local sessions
30-day Daily archive
Daily uses a deterministic date seed so the same date produces the same 20-question set on this build.
Quick 10
Untimed accuracy-first warm-up. Choose any skill and difficulty.
Sprint 60
Solve as many as you can in one minute. Correct/min and accuracy stay separate.
Standard 120
Fixed four-operation ranges and two minutes for repeatable like-for-like practice.
Daily 20
Twenty deterministic questions with a two-minute clock and date archive.
Adaptive 20
Difficulty rises after consecutive correct answers and falls after misses.
Weak Facts
Exact missed questions are stored locally and retire after three correct reviews.
Measurement note: typing speed, mobile keyboard layout, browser scheduling and device input latency affect observed response time. Compare like-for-like sessions on the same setup rather than treating browser timing as a pure measure of mathematical ability.