Internet pundits are complaining that caution lengths are longer in 2025 than ever before. Given that people tend to remember cases when something exceptional happens and forget the many times it doesn’t, this question just begs to be answered by statistics.
Let’s go to the caution length data.
Table of contents
Caution Overview 2001-2025
To start our investigation of whether caution lengths are increasing, I generated an overview of cautions and caution laps from 2001-2025. I started in 2001 because that was the year when 36 races became the standard for a full season.
But first a warning: The 2025 season is only 19.4% complete. As I’ve said before, you cannot claim a trend from the first half dozen (or half dozen plus one) races of a season. So don’t get too bent out of shape by the data I’m about to show.
The table below summarizes total laps run (including overtime and shortened races), total caution laps, and the percent of laps run under caution. The 2025 season includes only the first seven races.
Year | Total Cautions | Total Laps | Total Caution Laps | % Caution Laps | |
---|---|---|---|---|---|
0 | 2001 | 266 | 10854 | 1520 | 14.00 |
1 | 2002 | 269 | 10695 | 1572 | 14.70 |
2 | 2003 | 315 | 10668 | 1813 | 16.99 |
3 | 2004 | 313 | 10755 | 1774 | 16.49 |
4 | 2005 | 373 | 10737 | 1783 | 16.61 |
5 | 2006 | 346 | 10660 | 1580 | 14.82 |
6 | 2007 | 343 | 10582 | 1616 | 15.27 |
7 | 2008 | 321 | 10726 | 1445 | 13.47 |
8 | 2009 | 305 | 10492 | 1457 | 13.89 |
9 | 2010 | 265 | 10778 | 1321 | 12.26 |
10 | 2011 | 278 | 10650 | 1357 | 12.74 |
11 | 2012 | 216 | 10442 | 1128 | 10.80 |
12 | 2013 | 287 | 10553 | 1463 | 13.86 |
13 | 2014 | 303 | 10541 | 1570 | 14.89 |
14 | 2015 | 298 | 10425 | 1600 | 15.35 |
15 | 2016 | 269 | 10523 | 1469 | 13.96 |
16 | 2017 | 296 | 10581 | 1485 | 14.03 |
17 | 2018 | 247 | 10250 | 1328 | 12.96 |
18 | 2019 | 248 | 10255 | 1292 | 12.60 |
19 | 2020 | 282 | 9914 | 1433 | 14.45 |
20 | 2021 | 258 | 9200 | 1289 | 14.01 |
21 | 2022 | 302 | 9483 | 1596 | 16.83 |
22 | 2023 | 252 | 9375 | 1329 | 14.18 |
23 | 2024 | 254 | 9744 | 1469 | 15.08 |
24 | 2025 | 56 | 1808 | 364 | 20.13 |
The first significant data is the far-right column. Since 2001, the percentage of laps run under caution has varied from around 12% to 17% of all laps run. This year, that percentage is 20.1%.
In my opinion, you can see data trends better with a graph.
Doesn’t That Prove It?
It proves that the percentage of caution laps is higher (so far) this year than previously. But this number includes two factors:
- The total number of cautions. That’s different than longer cautions. That’s more cautions. The rate of cautions is higher this year than in the past. If the current rate of cautions continues, the Cup Series is on track for a total of 288 cautions for the full season. That’s compared to about 250 cautions in 2023 and 2024. More cautions means more totall caution laps.
- Caution length. The second factor is the length of each caution. That’s the data we want.
Average Caution Length by Caution Type
The table below shows you the average caution length by type of caution. I’ve also noted the shortest and longest cautions. Sigma is the standard deviation, which tells us how much variation there is relative to the mean. You can’t have a value of sigma when there’s only one data point in a category.
Reason | Total Cautions | Average Length (Laps) | Shortest Caution (Laps) | Longest Caution (Laps) | Sigma |
---|---|---|---|---|---|
Accident | 22 | 6.00 | 1 | 13 | 2.37 |
Debris | 3 | 4.67 | 3 | 8 | 2.89 |
Engine | 2 | 6.50 | 5 | 8 | 2.12 |
Mechanical | 2 | 7.00 | 5 | 9 | 2.83 |
Stage End | 13 | 7.38 | 3 | 12 | 2.50 |
Spin | 4 | 4.75 | 4 | 5 | 0.50 |
Stalled | 1 | 9.00 | 9 | 9 | nan |
Tire Issue | 5 | 5.80 | 5 | 6 | 0.45 |
Weather | 1 | 14.00 | 14 | 14 | nan |
Wheel Issue | 3 | 8.00 | 6 | 11 | 2.65 |
Those numbers by themselves don’t tell you anything: Let’s compare them with last year’s numbers.
Reason | Total Cautions | Average Length (Laps) | Shortest Caution (Laps) | Longest Caution (Laps) | Sigma |
---|---|---|---|---|---|
Accident | 123 | 5.50 | 1 | 15 | 2.36 |
Competition | 1 | 17.00 | 17 | 17 | nan |
Debris | 2 | 5.00 | 5 | 5 | 0.00 |
Mechanical | 5 | 4.80 | 3 | 7 | 1.48 |
Stage End | 61 | 6.34 | 2 | 13 | 2.50 |
Spin | 32 | 5.38 | 1 | 11 | 1.66 |
Stalled | 3 | 4.00 | 2 | 6 | 2.00 |
Tire Issue | 20 | 6.75 | 2 | 16 | 3.92 |
Weather | 2 | 4.00 | 4 | 4 | 0.00 |
Wheel Issue | 5 | 5.60 | 2 | 8 | 2.19 |
You can see that some types of cautions are longer in 2025 while others are shorter. Don’t put too much emphasis on categories for which there are only a handful of cautions.
The average accident caution length is up in 2025 primarily because of one 13-lap caution after ‘The Big One’ happened at Phoenix, of all places. No other caution due to an accident lasted more than eight laps.
That 13-lap caution was the massive, very unusual crash at Phoenix. No other caution due to an accident lasted more than eight laps. As usual, this is again a consequence of a small number of data points. One 13-lap caution out of 22 makes a much larger impact than when it is one out of 123 cautions.
In 2024, the average caution length for an accident was 5.5 laps. Since 2017, the average lengths of accident cautions has ranged between 4.9 and 5.0. So there is an increase, but we’re talking about an average of a half lap.
While the average length of a caution due to an accident is 0.5 laps higher than last year, it is still less than the average accident caution length was in 2002: 6.34 laps. The concern is that accidents always comprise the most cautions, so even a half a lap per caution can translate to 30 extra caution laps a season.
Some Caution Lengths Can’t Be Helped
There are some cases where there isn’t much NASCAR can do to shorten cautions.
Weather
When a caution is due to weather, I can make arguments on both sides of moving quickly to a red flag. No one wants to lose racing laps to circling under caution. However, keeping cars on track helps keep the track drier and could lead to faster resumption of racing.
Stalls
There’s no controlling where a car stalls out. If it happens at the enterance to pit lane, the caution has to be longer because no one can pit until the stalled car is removed.
Accidents
An accident involving 20 cars will always take longer to clean up than an accident involving two cars. How badly damaged the cars are determines whether they can be towed or must be put on a flat-bed.
My One Concern About Caution Lengths
During the stage racing era (2017-present), the average stage-end caution length ranged from 5.29 laps (2021) to 6.41 laps (2023.) In 2025, the average stage caution so far has lasted 7.39 laps. The 13 stage-end cautions break down into:
- 1 12-lap caution
- 1 11-lap caution
- 1 10-lap caution
- 1 8-lap caution
- 6 7-lap cautions
- 1 6-lap caution
- 1 4-lap caution
- 1 3-lap caution
The three longest stage-end cautions were at Martinsville (12 laps, where NASCAR took extra time to try to remove marbles from the racing surface) and two at Phoenix. At both tracks, softer tires create more marbles and necessitate cleaning during stage breaks.
So do you want softer tires and better racing or shorter stage breaks? There are never simple answers.
Those three cautions comprise a full 1/3 of the total laps lost to stage end cautions in 2025. Without those three cautions, the average stage-end caution would be 6.3 laps, which is consistent with previous years.
For the Nerds: Bonus Stage-End Caution Lengths Graph
Those wanting ore detail will find it in the box plot of the stage-end caution lengths for each year. The only thing I couldn’t figure out how to do was indicate how many cautions each diamond represents.
Although the average stage-end caution is about one lap longer this year, none of the inidividual caution lengths are as high (or low) as seen in previous years.
Caution Lengths โ TL; DR
- The percentage of laps run under caution in 2025 is โ after just seven races โ the highest it’s been at 20.1%.
- One reason is because 2025 has had more than its share of cautions so far this year.
- This is the first time since 2011 that there have been more than five cautions in Stage 1 at a Phoenix race.
- If the current rate of cautions continues, the Cup Series is on track for a total of 288 cautions for the full season. That’s almost 40 more cautions than either of the last two years.
- More cautions is distinct from caution lengths.
- Caution lengths are creeping up a bit. They’re down for spins, debris and tire issues. They’re up for accidents, wheel issues and stage-end cautions.
- The largest increase in caution lengths is in stage-end cautions, which are up about one lap per caution.
- The longest stage-end cautions were at Martinsville and Phoenix. At both tracks, softer tires create more marbles and necessitate cleaning during stage breaks. So do you want softer tires and better racing or shorter stage breaks?
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I have never liked stage racing and the artificial caution, etc.
But the simple fact that the average stage end is 7 laps is crazy. Why isn’t it 4 laps by rule?
Slow-down lap, 2 pit laps, 1 formation lap and then boom, you’re back to racing?
I know, commercials, right? I get it, but 7 laps is just silly.
My perception of the caution laps near the end of a stage is. Caution comes out with 14 laps to go. NASCAR seems to burn 11 of those so there is a 3 lap shootout. Why? I hate when they seem to do this on purpose at Daytona and Dega. They love to see drivers lose their minds running in P6 to get another position. What they usually get is getting in a wreck. I donโt like this manufactured drama. Iโm going out on a limb here and say owners donโt like it either. It costs money to fix cars.