How long does the Trail Making Test B take?
About 3 to 5 minutes, as listed in the test library.
Executive Function
Trail Making Test B
Measure set shifting and cognitive flexibility with a browser-native Trail Making Test Part B.
Useful for executive-function research, frontal-lobe studies, and batteries that compare TMT-B against TMT-A.
Free to start: 10 free participants per account, then $0.99 per participant for academic research, or any yearly plan. Preview any test free after you sign up.
Executive function3-5 minTimed: desktop or laptop with a mouse or trackpad
1
A
2
B
3
C
Alternate: 1-A-2-B-3-C...
What this task measures
Measures executive function and cognitive flexibility by asking participants to alternate between numbers and letters (1-A-2-B-3-C...).
Core constructs
- Set shifting
- Cognitive flexibility
- Divided attention
- Executive function
- Sequencing ability
Research fit
- Frontal lobe dysfunction detection
- Dementia differential diagnosis
- ADHD executive function assessment
- Traumatic brain injury severity
- Neuropsychological battery standard
Paradigm overview
Trail Making Test Part B measures executive function and cognitive flexibility. Participants must connect circles by alternating between numbers and letters in ascending order (1-A-2-B-3-C-...8-H), requiring constant switching between two cognitive sets. The 16 circles are randomly positioned on a canvas.
The critical cognitive demand is set-shifting: participants must maintain two parallel sequences (numeric and alphabetic), track their current position in each, and switch between them on every step. This engages the dorsolateral prefrontal cortex and is one of the most widely used clinical measures of executive function.
The TMT B-A difference (Part B time minus Part A time) is a commonly used derived measure that isolates the executive function component by subtracting out the motor speed contribution measured by Part A. This difference score is particularly sensitive to frontal lobe pathology.
Key scoring outputs
Completion Time
msTotal time from first click to connecting the final circle. Primary measure of executive-mediated processing speed.
Lower is better
Completion Time (sec)
secondsSame as completion time, converted to seconds.
Lower is better
Errors
countIncorrect clicks (wrong circle). In TMT-B, errors often reflect sequencing or set-switching failures.
Lower is better
Total Circles
countNumber of circles in the trail (16 for TMT-B: 8 numbers + 8 letters).
Informational
Running this test
Settings you can change
This test runs with fixed settings.
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Devices and languages
- Timed test: participants need a desktop or laptop with a mouse or trackpad. Participant devices
- Task text: English and Italian.
- Available on: Every plan, including the free plan.
- Recruiting online? See the setup guides for Prolific, Sona Systems, CloudResearch Connect and Qualtrics.
Cite this test
Paradigm source: Reitan (1958).
ConductCognition versions: task version 1.0.0, scoring version 1.0.0. Every export records the versions each session used, for a methods section.
Source papers
Tombaugh TN (2004). Trail Making Test A and B: Normative data stratified by age and education. Archives of Clinical Neuropsychology, 19(2):203-214.
Paradigm source
Research FAQ
Common questions about this online cognitive test
What device does a participant need?
Timed test: participants need a desktop or laptop with a mouse or trackpad. The browser must be Chrome, Edge, Firefox or Safari.
What scores does it produce?
Completion Time, Completion Time (sec), Errors and Total Circles. Each session is also marked valid, needs review or invalid, with the reason.
Which languages can participants use?
The test's own text is in English and Italian. Italian participant pages come with yearly plans.
Is this a clinical test?
No. ConductCognition is for research use only. It runs, scores and exports the test; clinical interpretation is outside the platform.
Every test: the full test list.
Run this test in your next study
Start free with 10 free participants on any test, then use participant credits or a yearly plan.