Trail Making Test Online: Part A and Part B
The trail making test is one of the most widely used measures of processing speed and attention switching. Part A is a straight sequence — 1, 2, 3 — and measures how fast you can find and move. Part B alternates numbers and letters — 1, A, 2, B — and that alternation is the whole point: it forces you to hold two sequences at once and jump between them. The gap between your Part A and Part B times is where task-switching shows up.
Not a diagnostic tool. The trail making test has a long clinical history — standardized versions are used in dementia, MCI, brain-injury and stroke screening, with age-matched norms and trained administration. This online version has none of that: it is not validated, not normed, and it cannot screen for or diagnose any condition. It is a practice and self-tracking exercise, not a diagnostic instrument.
A quiet round of Trail Making Test — Part A. When you start, everything else fades — just you and the task.
No sign-up needed. Press Esc to exit anytime.
Tip
Search while your finger is still moving. The travel between two circles is time you are going to spend anyway. Locating the next label during that movement, rather than after the tap lands, is where the gap between a fast run and a slow one quietly accumulates.
Everything here is free
Every test, every difficulty, no limit and no account. If it is useful to you, you can chip in — entirely optional, and nothing changes either way.
Trail Making Test: what it is and where it comes from
What is the Trail Making Test? The Trail Making Test has you connect circles in order — numbers only in Part A, alternating numbers and letters in Part B. It comes from the Army Individual Test Battery (1944), brought into wide use by Reitan (1958); the gap between parts reflects switching cost. Focani's free browser version runs 15 targets per session and needs no sign-up.
| Specification | Trail Making Test |
|---|---|
| Primary cognitive domain | Scanning speed — in the “Finding things fast” group |
| Original citation | Army Individual Test Battery (1944); brought into wide use by Reitan, R. M. (1958). Validity of the Trail Making Test as an indicator of organic brain damage. Perceptual and Motor Skills, 8, 271–276.doi:10.2466/pms.1958.8.3.271 |
| Core dependent metrics | Completion time (s) · False alarms (commission errors) |
| Standard stimulus / trial parameters | Pencil on paper with an examiner present who corrects each error as it happens. Age- and education-stratified norms exist and are the reason clinicians use it. |
| This version | Part A — 15 targets · Part B — 16 targets |
| Browser adaptation notes | Pointer or touch instead of pencil, no examiner, and fewer targets than the standard 25 per part. Those norms do not apply to this version. |
Full sources for every test, and what each version changes, are on the instructors page.
How to play
- Circles are scattered across the field, each labeled with a number or a letter.
- Part A: tap them in numerical order — 1, 2, 3, and so on.
- Part B: alternate between the two sequences — 1, A, 2, B, 3, C…
- Wrong taps count against your accuracy. Finish the trail to see your time and score.
Trail Making Test tips
Ways to play it better — each one comes from how this version actually scores, not from general advice about concentration.
Search while your finger is still moving
The travel between two circles is time you are going to spend anyway. Locating the next label during that movement, rather than after the tap lands, is where the gap between a fast run and a slow one quietly accumulates.
Don't trace the trail
Nothing has to be drawn between the circles — the name comes from the paper version, where you did drag a pencil. Letting your eyes jump straight to the next label instead of following an imaginary line saves the entire detour.
Don't slow down to avoid a wrong tap
With Part A's fifteen nodes, a single wrong tap takes just over six percent off the accuracy multiplier. This test is scored speed-led, so hunting slowly for a label that is hiding usually costs more than the wrong tap would have.
One caveat worth knowing: a change of strategy moves your score for reasons that have nothing to do with attention. Your dashboard reads each session against your own recent ones, so if you adopt something from this list, give it a few sessions before reading anything into the trend.
Frequently asked questions
What is the trail making test?+
A timed connect-the-sequence task. Part A measures visual search and processing speed; Part B adds an alternation rule that requires switching between two sequences, which brings executive function and attention switching into play.
What's the difference between Part A and Part B?+
Part A is numbers only. Part B alternates numbers and letters, so you have to keep two counters running and swap between them on every step. Part B is reliably slower for everyone — the interesting number is how much slower you personally get, since that difference isolates the switching cost from raw speed.
Is the trail making test the same as a task switching test?+
Part B is one of the classic ways task switching gets operationalized, so the two overlap heavily. A dedicated task-switching test usually alternates abstract rules (odd/even, then high/low); TMT Part B alternates two familiar sequences instead, which makes it far easier to explain and just as demanding to do.
Is this a medical or diagnostic test?+
No. The trail making test has a long clinical history — standardized versions are used in screening for dementia, mild cognitive impairment, traumatic brain injury, and stroke, always with age-matched norms and trained administration. This online version has none of that. It is a practice and self-tracking exercise, not validated, not normed, and it cannot screen for or diagnose any condition. If you have concerns about your cognition, talk to a professional.
Where this fits
- Processing Speed Test — Sequenced movement plus, in Part B, switching between two sequences. The gap between your Part A and Part B time isolates the cost of switching from raw speed.
Related attention paradigms
Finding things fast — closest to this one
- Schulte Table — practices and measures visual search speed and peripheral vision.
- Visual Search — practices and measures scanning speed and sustained attention.
- Cancellation Task — practices and measures visual scanning and selective attention.