What is the Trail Making Test?
The Trail Making Test is a connect-the-circles task in two parts. In Part A you join 25 numbered circles in order, 1 to 25. In Part B you alternate between numbers and letters: 1, A, 2, B, 3, C and on to 13, still 25 circles. The pencil-and-paper original dates from the 1940s, when it was part of a US Army test battery, and it is still used by psychologists. This page is a recreational version of the same idea.
How this version works
Choose Part A or Part B and press Start. The circles appear at random places on the board, a new layout every time, and you tap them in order. A line follows you from circle to circle. Tapping the wrong circle flashes it red and counts a mistake; the trail waits for the right one. The number or letter to find next is shown above the board.
How is your result calculated?
The clock starts in the frame the circles first appear and stops at your last correct tap, using the timestamp your browser gives that tap. Your result is that time, with your mistakes counted beside it. If you finish both parts in one visit, you also see your best Part B time minus your best Part A time.
What is a normal Trail Making Test time?
On the paper test, adults under 35 take about 23 to 24 seconds for Part A and about 50 seconds for Part B on average, and both times grow with age. These are the averages Tom Tombaugh published in 2004 from 911 healthy adults aged 18 to 89, still one of the most used sets of norms:
| Age | Part A (seconds) | Part B (seconds) |
|---|---|---|
| 18–24 | 22.9 | 49.0 |
| 25–34 | 24.4 | 50.7 |
| 35–44 | 28.5 | 58.5 |
| 45–54 | 31.8 | 63.8 |
| 55–59 | 31.7 | 68.7 |
| 60–64 | 31.3 | 64.6 |
| 65–69 | 33.8 | 67.1 |
| 70–74 | 40.1 | 86.3 |
| 75–79 | 41.7 | 100.7 |
| 80–84 | 55.3 | 132.2 |
| 85–89 | 63.5 | 140.5 |
From age 55 the figures are for people with 12 or more years of education; those with less were a few seconds slower on Part A and more on Part B. Use the table as a rough guide only: the paper test has a fixed layout, a pencil and an examiner who points out mistakes, while here the layout is new each time and you tap a screen.
What does the Trail Making Test measure?
Part A is mostly about visual search and speed: finding the next number and getting there. Part B asks for the same plus switching between two sequences, holding your place in the numbers while you find the next letter. That is why Part B usually takes longer, and why the difference between the two parts is the number psychologists pay attention to: it isolates the cost of switching.
What this test does not measure
It measures how fast you tapped 25 circles in order, on your device, in one sitting. It isn't the clinical test: that uses a printed sheet, a pencil, a fixed layout and an examiner who corrects mistakes on the spot, and its results are compared with norms for age and education. A phone screen and random layouts change all of that, so the table above is a guide rather than a yardstick, and your time says nothing about any condition. For a similar find-in-order task, try the Schulte Table; for another switching task, the Digit Symbol Substitution Test.