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BOSTON MARATHON 2025

Brendan O'Sullivan

Bib: 27938•M

MA

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

Start
0:00:00
Race begins
5K· 3.11 mi
31:03
Rank: #25554
Start → 5K
10:00/mi
31:03 split
10K· 6.21 mi
1:01:51
Rank: #25319 (+235)
5K → 10K
9:55/mi
30:48 split
15K· 9.32 mi
1:32:11
Rank: #25027 (+292)
10K → 15K
9:46/mi
30:20 split
20K· 12.43 mi
2:01:57
Rank: #24568 (+459)
15K → 20K
9:35/mi
29:46 split
Half· 13.11 mi
2:08:26
Rank: #24516 (+52)
20K → Half
9:30/mi
6:29 split
25K· 15.53 mi
2:31:53
Rank: #24176 (+340)
Half → 25K
9:40/mi
23:27 split
30K· 18.64 mi
3:03:14
Rank: #23760 (+416)
25K → 30K
10:05/mi
31:21 split
20M
3:17:55
Rank: #23717 (+43)
30K → 20M
10:48/mi
14:41 split
21M
3:29:38
Rank: #23682 (+35)
20M → 21M
11:43/mi
11:43 split
35K· 21.75 mi
3:38:17
Rank: #23761 (-79)
21M → 35K
11:34/mi
8:39 split
23M
3:52:38
Rank: #23789 (-28)
35K → 23M
11:28/mi
14:21 split
24M
4:05:06
Rank: #23944 (-155)
23M → 24M
12:28/mi
12:28 split
40K· 24.85 mi
4:15:37
Rank: #24040 (-96)
24M → 40K
12:18/mi
10:31 split
25.2M
4:19:34
Rank: #24025 (+15)
40K → 25.2M
11:27/mi
3:57 split
Finish· 26.22 mi
4:30:09
Rank: #24029 (-4)
25.2M → Finish
10:23/mi
10:35 split

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time2:08:26
Pace9:48 /mi
2nd Half
Distance13.11 mi
Time2:21:43
Pace10:49 /mi
📊Positive Split: 10.3% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi11:49:1831:0310:0031:03
10:00
-
10K
6.21 mi12:20:061:01:519:5730:48
9:55
-0:05
15K
9.32 mi12:50:261:32:119:5330:20
9:46
-0:09
20K
12.43 mi13:20:122:01:579:4929:46
9:35
-0:11
Half
13.11 mi13:26:412:08:269:486:29
9:30
-0:05
25K
15.53 mi13:50:082:31:539:4723:27
9:40
+0:10
30K
18.64 mi14:21:293:03:149:5031:21
10:05
+0:25
20M
20.00 mi14:36:103:17:559:5414:41
10:48
+0:43
21M
21.00 mi14:47:533:29:389:5911:43
11:43
+0:55
35K
21.75 mi14:56:323:38:1710:028:39
11:34
-0:09
23M
23.00 mi15:10:533:52:3810:0714:21
11:28
-0:06
24M
24.00 mi15:23:214:05:0610:1312:28
12:28
+1:00
40K
24.85 mi15:33:524:15:3710:1710:31
12:18
-0:10
25.2M
25.20 mi15:37:494:19:3410:183:57
11:27
-0:51
Finish
26.22 mi15:48:244:30:0910:1910:35
10:23
-1:04

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

9:30 /mi

Average Pace

10:19 /mi

Slowest Pace

12:28 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

1:30:02

33% of race

Time at Steady Pace

1:58:28

44% of race

Time at Slower Pace

1:01:39

23% of race

Average Pace: 10:18 /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 mi11:49:1831:0310:0031:03
10:00
#25554
10K
6.21 mi12:20:061:01:519:5730:48
9:55
#25319
15K
9.32 mi12:50:261:32:119:5330:20
9:46
#25027
20K
12.43 mi13:20:122:01:579:4929:46
9:35
#24568
Half
13.11 mi13:26:412:08:269:486:29
9:30
#24516
25K
15.53 mi13:50:082:31:539:4723:27
9:40
#24176
30K
18.64 mi14:21:293:03:149:5031:21
10:05
#23760
20M
20.00 mi14:36:103:17:559:5414:41
10:48
#23717
21M
21.00 mi14:47:533:29:389:5911:43
11:43
#23682
35K
21.75 mi14:56:323:38:1710:028:39
11:34
#23761
23M
23.00 mi15:10:533:52:3810:0714:21
11:28
#23789
24M
24.00 mi15:23:214:05:0610:1312:28
12:28
#23944
40K
24.85 mi15:33:524:15:3710:1710:31
12:18
#24040
25.2M
25.20 mi15:37:494:19:3410:183:57
11:27
#24025
Finish
26.22 mi15:48:244:30:0910:1910:35
10:23
#24029
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallMalesM18-39Seg. OverallSeg. MalesSeg. M18-39
5K3.11 mi3.11 mi25554149811498124460(Top 86%)14465(Top 90%)14465(Top 256%)
10K6.21 mi3.10 mi25319+23514848+13314848+13325123(Top 88%)14759(Top 92%)14759(Top 262%)
15K9.32 mi3.11 mi25027+29214725+12314725+12324460(Top 86%)14465(Top 90%)14465(Top 256%)
20K12.43 mi3.11 mi24568+45914494+23114494+23123149(Top 81%)13866(Top 86%)13866(Top 246%)
Half13.11 mi0.68 mi24516+5214470+2414470+2423565(Top 83%)14042(Top 87%)14042(Top 249%)
25K15.53 mi2.42 mi24176+34014308+16214308+16222424(Top 79%)13478(Top 84%)13478(Top 239%)
30K18.64 mi3.11 mi23760+41614094+21414094+21421868(Top 77%)13106(Top 81%)13106(Top 232%)
20M20.00 mi1.36 mi23717+4314048+4614048+4623179(Top 82%)13611(Top 85%)13611(Top 241%)
21M21.00 mi1.00 mi23682+3514021+2714021+2723058(Top 81%)13476(Top 84%)13476(Top 239%)
35K21.75 mi0.75 mi23761-7914051-3014051-3025184(Top 89%)14430(Top 90%)14430(Top 256%)
23M23.00 mi1.25 mi23789-2814041+1014041+1024183(Top 85%)13930(Top 86%)13930(Top 247%)
24M24.00 mi1.00 mi23944-15514106-6514106-6526273(Top 92%)14950(Top 93%)14950(Top 265%)
40K24.85 mi0.85 mi24040-9614132-2614132-2625376(Top 89%)14453(Top 90%)14453(Top 256%)
25.2M25.20 mi0.35 mi24025+1514122+1014122+1021930(Top 77%)12761(Top 79%)12761(Top 226%)
Finish26.22 mi1.02 mi24029-414110+1214110+1224002(Top 85%)13770(Top 86%)13770(Top 244%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 86%
×21story building
+97ft-345ft

Overall

24460

Males

14465

M18-39

14465

5K→10K

3.1 - 6.2 mi

Top 88%
×5story building
+79ft-138ft

Overall

25123

Males

14759

M18-39

14759

10K→15K

6.2 - 9.3 mi

Top 86%
×3story building
+67ft-78ft

Overall

24460

Males

14465

M18-39

14465

15K→20K

9.3 - 12.4 mi

Top 81%
×5story building
+106ft-86ft

Overall

23149

Males

13866

M18-39

13866

20K→Half

12.4 - 13.1 mi

Top 83%
×2story building
+19ft-37ft

Overall

23565

Males

14042

M18-39

14042

Half→25K

13.1 - 15.5 mi

Top 79%
×4story building
+66ft-88ft

Overall

22424

Males

13478

M18-39

13478

25K→30K

15.5 - 18.6 mi

Top 77%
×9story building
+181ft-148ft

Overall

21868

Males

13106

M18-39

13106

30K→20M

18.6 - 20.0 mi

Top 82%
×5story building
+64ft-50ft

Overall

23179

Males

13611

M18-39

13611

20M→21M

20.0 - 21.0 mi

Top 81%
×8story building
+106ft-24ft

Overall

23058

Males

13476

M18-39

13476

21M→35K

21.0 - 21.8 mi

Top 89%
×7story building
+17ft-86ft

Overall

25184

Males

14430

M18-39

14430

35K→23M

21.8 - 23.0 mi

Top 85%
×5story building
+23ft-63ft

Overall

24183

Males

13930

M18-39

13930

23M→24M

23.0 - 24.0 mi

Top 92%
×6story building
+12ft-82ft

Overall

26273

Males

14950

M18-39

14950

24M→40K

24.0 - 24.9 mi

Top 89%
×1story
+6ft-20ft

Overall

25376

Males

14453

M18-39

14453

40K→25.2M

24.9 - 25.2 mi

Top 77%
×1story
+13ft-16ft

Overall

21930

Males

12761

M18-39

12761

25.2M→Finish

25.2 - 26.2 mi

Top 85%
×2story building
+22ft-21ft

Overall

24002

Males

13770

M18-39

13770

Passing Analysis

Category:
Athletes Passed
2294
Passed By
769
Net Change
+1525
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#25554
5K → 10K32489+235#25554#25319
10K → 15K31624+292#25319#25027
15K → 20K4645+459#25027#24568
20K → Half575+52#24568#24516
Half → 25K3488+340#24516#24176
25K → 30K43418+416#24176#23760
30K → 20M9754+43#23760#23717
20M → 21M8348+35#23717#23682
21M → 35K2099-79#23682#23761
35K → 23M5785-28#23761#23789
23M → 24M12167-155#23789#23944
24M → 40K14110-96#23944#24040
40K → 25.2M2712+15#24040#24025
25.2M → Finish4145-4#24025#24029
TOTALS2294769+1525
📊

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