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BOSTON MARATHON 2025

Jan Lucas Clasen

Bib: 5879•M

0:00
0:00
/ mi
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Overall
#0 / 28404
Gender (Male)
#0 / 16105
Division (M18-39)
#0 / 5642
Race Day Weather
50°/40°F
broken clouds

⏱️ Race Timeline

Course Elevation
7–469 ft
≈
×2stacked redwood trees
•▲ 890 ft climb · ▼ 1342 ft descent
Ribbon color based on
FasterSteadySlower· vs. your average pace
Start
0:00
Race begins
5K· 3.11 mi
7:45/mi
24:06
↑ 97↓ 3451.5%
10K· 6.21 mi
8:01/mi
49:00
↑ 79↓ 1380.4%
15K· 9.32 mi
8:01/mi
1:13:55
↑ 67↓ 78
20K· 12.43 mi
7:55/mi
1:38:31
↑ 106↓ 860.1%
Half· 13.11 mi
7:33/mi
1:43:40
↑ 19↓ 370.5%
25K· 15.53 mi
7:53/mi
2:02:48
↑ 66↓ 880.2%
30K· 18.64 mi
13:25/mi
2:44:30
↑ 181↓ 1480.2%
20M
14:29/mi
3:04:11
↑ 64↓ 500.2%
21M
13:30/mi
3:17:41
↑ 106↓ 241.6%
35K· 21.75 mi
11:15/mi
3:26:06
↑ 17↓ 861.7%
23M
14:40/mi
3:44:28
↑ 23↓ 630.6%
24M
8:21/mi
3:52:49
↓ 821.3%
40K· 24.85 mi
8:50/mi
4:00:22
↓ 200.3%
25.2M
8:39/mi
4:03:21
↑ 13↓ 160.2%
Finish· 26.22 mi
7:37/mi
4:11:07
↑ 22↓ 21

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time1:43:40
Pace7:54 /mi
2nd Half
Distance13.11 mi
Time2:27:27
Pace11:15 /mi
📊Positive Split: 42.2% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi10:32:4524:067:4524:06
7:45
-
10K
6.21 mi10:57:3949:007:5324:54
8:01
+0:16
15K
9.32 mi11:22:341:13:557:5624:55
8:01
0:00
20K
12.43 mi11:47:101:38:317:5624:36
7:55
-0:06
Half
13.11 mi11:52:191:43:407:545:09
7:33
-0:22
25K
15.53 mi12:11:272:02:487:5419:08
7:53
+0:20
30K
18.64 mi12:53:092:44:308:4941:42
13:25
+5:32
20M
20.00 mi13:12:503:04:119:1319:41
14:29
+1:04
21M
21.00 mi13:26:203:17:419:2513:30
13:30
-0:59
35K
21.75 mi13:34:453:26:069:298:25
11:15
-2:15
23M
23.00 mi13:53:073:44:289:4618:22
14:40
+3:25
24M
24.00 mi14:01:283:52:499:428:21
8:21
-6:19
40K
24.85 mi14:09:014:00:229:407:33
8:50
+0:29
25.2M
25.20 mi14:12:004:03:219:392:59
8:39
-0:11
Finish
26.22 mi14:19:464:11:079:357:46
7:37
-1:02

Checkpoints & Pacing

📈Pace Line

Pace Progression

Track your pace changes throughout the race. Dot colors mark your quickest to easiest segments, relative to your own pace.

Fastest Pace

7:33 /mi

Average Pace

9:35 /mi

Slowest Pace

14:40 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

0:00

0% of race

Time at Steady Pace

2:29:27

60% of race

Time at Slower Pace

1:41:40

40% of race

Average Pace: 9:35 /mi

Loading chart...
Faster pace (< avg)
Steady pace (≈ avg)
Slower pace (> avg)

🎨Heatmap

Pace Heatmap

Where you sped up and eased off relative to your own pace across the race. Colors are relative to your own range, not to other runners.

Loading...
0mi6.6mi13.1mi19.7mi26.2mi
Pace:
Faster
Steady
Slower

Click or hover over segments to see details

✨Sparklines

Checkpoint Splits with Pace Trends

Overall Pace Trend

CheckpointDistanceTime of DayTimeAvg PaceSegmentPaceTrendRank
5K
3.11 mi10:32:4524:067:4524:06
7:45
#14435
10K
6.21 mi10:57:3949:007:5324:54
8:01
#15533
15K
9.32 mi11:22:341:13:557:5624:55
8:01
#15763
20K
12.43 mi11:47:101:38:317:5624:36
7:55
#15347
Half
13.11 mi11:52:191:43:407:545:09
7:33
#15162
25K
15.53 mi12:11:272:02:487:5419:08
7:53
#14761
30K
18.64 mi12:53:092:44:308:4941:42
13:25
#20013
20M
20.00 mi13:12:503:04:119:1319:41
14:29
#21508
21M
21.00 mi13:26:203:17:419:2513:30
13:30
#21958
35K
21.75 mi13:34:453:26:069:298:25
11:15
#22092
23M
23.00 mi13:53:073:44:289:4618:22
14:40
#22782
24M
24.00 mi14:01:283:52:499:428:21
8:21
#22488
40K
24.85 mi14:09:014:00:229:407:33
8:50
#22300
25.2M
25.20 mi14:12:004:03:219:392:59
8:39
#22179
Finish
26.22 mi14:19:464:11:079:357:46
7:37
#21868
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallMalesM18-39Seg. OverallSeg. MalesSeg. M18-39
5K3.11 mi3.11 mi14435102191021916194(Top 57%)10900(Top 68%)10900(Top 193%)
10K6.21 mi3.10 mi15533-109810632-41310632-41316588(Top 58%)11070(Top 69%)11070(Top 196%)
15K9.32 mi3.11 mi15763-23010723-9110723-9116194(Top 57%)10900(Top 68%)10900(Top 193%)
20K12.43 mi3.11 mi15347+41610526+19710526+19714252(Top 50%)9994(Top 62%)9994(Top 177%)
Half13.11 mi0.68 mi15162+18510442+8410442+8412131(Top 43%)9103(Top 57%)9103(Top 161%)
25K15.53 mi2.42 mi14761+40110238+20410238+20413040(Top 46%)9314(Top 58%)9314(Top 165%)
30K18.64 mi3.11 mi20013-525212425-218712425-218727082(Top 95%)15469(Top 96%)15469(Top 274%)
20M20.00 mi1.36 mi21508-149513077-65213077-65227621(Top 97%)15674(Top 97%)15674(Top 278%)
21M21.00 mi1.00 mi21958-45013255-17813255-17825664(Top 90%)14709(Top 91%)14709(Top 261%)
35K21.75 mi0.75 mi22092-13413307-5213307-5224685(Top 87%)14202(Top 88%)14202(Top 252%)
23M23.00 mi1.25 mi22782-69013576-26913576-26927743(Top 98%)15699(Top 97%)15699(Top 278%)
24M24.00 mi1.00 mi22488+29413424+15213424+15213569(Top 48%)8941(Top 56%)8941(Top 158%)
40K24.85 mi0.85 mi22300+18813320+10413320+10415354(Top 54%)9602(Top 60%)9602(Top 170%)
25.2M25.20 mi0.35 mi22179+12113258+6213258+629725(Top 34%)6844(Top 42%)6844(Top 121%)
Finish26.22 mi1.02 mi21868+31113103+15513103+15510114(Top 36%)7051(Top 44%)7051(Top 125%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 57%
×21story building
+97ft-345ft

Overall

16194

Males

10900

M18-39

10900

5K→10K

3.1 - 6.2 mi

Top 58%
×5story building
+79ft-138ft

Overall

16588

Males

11070

M18-39

11070

10K→15K

6.2 - 9.3 mi

Top 57%
×3story building
+67ft-78ft

Overall

16194

Males

10900

M18-39

10900

15K→20K

9.3 - 12.4 mi

Top 50%
×5story building
+106ft-86ft

Overall

14252

Males

9994

M18-39

9994

20K→Half

12.4 - 13.1 mi

Top 43%
×2story building
+19ft-37ft

Overall

12131

Males

9103

M18-39

9103

Half→25K

13.1 - 15.5 mi

Top 46%
×4story building
+66ft-88ft

Overall

13040

Males

9314

M18-39

9314

25K→30K

15.5 - 18.6 mi

Top 95%
×9story building
+181ft-148ft

Overall

27082

Males

15469

M18-39

15469

30K→20M

18.6 - 20.0 mi

Top 97%
×5story building
+64ft-50ft

Overall

27621

Males

15674

M18-39

15674

20M→21M

20.0 - 21.0 mi

Top 90%
×8story building
+106ft-24ft

Overall

25664

Males

14709

M18-39

14709

21M→35K

21.0 - 21.8 mi

Top 87%
×7story building
+17ft-86ft

Overall

24685

Males

14202

M18-39

14202

35K→23M

21.8 - 23.0 mi

Top 98%
×5story building
+23ft-63ft

Overall

27743

Males

15699

M18-39

15699

23M→24M

23.0 - 24.0 mi

Top 48%
×6story building
+12ft-82ft

Overall

13569

Males

8941

M18-39

8941

24M→40K

24.0 - 24.9 mi

Top 54%
×1story
+6ft-20ft

Overall

15354

Males

9602

M18-39

9602

40K→25.2M

24.9 - 25.2 mi

Top 34%
×1story
+13ft-16ft

Overall

9725

Males

6844

M18-39

6844

25.2M→Finish

25.2 - 26.2 mi

Top 36%
×2story building
+22ft-21ft

Overall

10114

Males

7051

M18-39

7051

Passing Analysis

Category:
Athletes Passed
2190
Passed By
9623
Net Change
-7433
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#14435
5K → 10K501148-1098#14435#15533
10K → 15K132362-230#15533#15763
15K → 20K45135+416#15763#15347
20K → Half1872+185#15347#15162
Half → 25K41615+401#15162#14761
25K → 30K25254-5252#14761#20013
30K → 20M61501-1495#20013#21508
20M → 21M12462-450#21508#21958
21M → 35K11145-134#21958#22092
35K → 23M9699-690#22092#22782
23M → 24M2940+294#22782#22488
24M → 40K1880+188#22488#22300
40K → 25.2M1210+121#22300#22179
25.2M → Finish3110+311#22179#21868
TOTALS21909623-7433
📊

Passing Visuals

Category:
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🔄Passing Circle

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🌊Position Flow

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🏃Race Lanes

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Public Race Data

Boston Athletic Association

Boston Athletic Association

Mika Timing

Mika Timing