How to use the lap time analyzer
- Paste your lap times, one per line, as minutes:seconds.thousandths such as 1:24.512, or just seconds such as 84.512.
- Optionally add sector times, one lap per line with the sectors separated by commas. Use the same number of sectors on every line.
- Read the best lap, the average, the median, the spread and the consistency. With sectors you also get the theoretical best lap.
- Use the table to see each lap's change from the one before and how far it is behind the best.
Formula
every time is converted to whole milliseconds
consistency = 1 - standard deviation / average lap (n - 1 in the deviation)
theoretical best = the fastest time in each sector, added together
Working in whole milliseconds keeps every sum exact. The theoretical best can never be slower than the best lap, because the best lap is made of sectors that are each at least as slow as the fastest of that sector.
Eight laps on one circuit
The default laps are 1:24.512, 1:23.874, 1:23.301, 1:24.120, 1:23.655, 1:22.998, 1:23.846 and 1:24.390. The best is lap 6 at 1:22.998. The average is 1:23.837, the median is 1:23.860, the slowest is 1:24.512 and the average of the best three is 1:23.318. The total is 11:10.696.
The sample standard deviation is 0.516 seconds, so the consistency is 1 - 0.516 / 83.837 = 99.38%. With sectors 28.1, 31.0, 25.4 and 27.9, 31.2, 25.1 and 28.3, 30.8, 25.5 the fastest sectors are 27.9, 30.8 and 25.1, so the theoretical best is 1:23.800.
Reading consistency
Consistency compares how much your lap times vary with how long a lap is. A figure close to 100% means laps are close to each other. It is sensitive to one slow lap such as an out lap or a lap with a mistake, so remove those first if you want to judge your normal pace.
The average of the best three laps is steadier than the single best lap, which may have been a lucky one. The gap between the best lap and the theoretical best shows how much time is left in putting your best sectors together.
Using sector times
If you have sector times from a timing system, enter them in the same lap order. The page checks that the sectors add up to the lap time and warns about laps that differ by more than 5 milliseconds. The theoretical best combines sectors from different laps, so it may not be possible in a single lap. For timing live, use the Stopwatch, and for planning a race, see the Race Time Predictor and the Pace Calculator.
More hobby and sport tools
For other hobbies, sports and music, try the Equivalent Exposure Calculator, Key Finder and Maidenhead Locator Converter.
Assumptions and limits
- Times have at most three decimals for the seconds, and every lap is between 1 millisecond and a few hours.
- Each lap is a full lap of the same course.
- The standard deviation uses n - 1, so it needs at least two laps.
- Sector lines, if given, must match the laps one for one.
Frequently asked questions
Why is the theoretical best faster than my best lap?
It adds the fastest time for each sector, and you rarely set all of those on one lap. It is a target to chase and not a time you are sure to reach.
How do I enter hours?
Write the time as hours:minutes:seconds, such as 1:02:03.5. Minutes and seconds must be below 60 in that form.
What does the change from the previous lap show?
It shows whether you got faster or slower. A minus sign means this lap was quicker than the one before it.
Why does the consistency number depend on lap length?
It compares the spread with the average lap. The same spread in seconds is a smaller share of a long lap, so it gives a higher percentage than on a short lap.