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BOSTON MARATHON 2025

Thomas Nilsson

Bib: 4563•M

0:00
0:00
/ mi
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Overall
#0 / 28404
Top 20%
Gender (Male)
#0 / 16105
Top 32%
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
20:17
Rank: #4045
Start → 5K
20:17 | 6:32/mi
10K· 6.21 mi
40:39
Rank: #4077 (-32)
5K → 10K
20:22 | 6:33/mi
15K· 9.32 mi
1:00:50
Rank: #3863 (+214)
10K → 15K
20:11 | 6:30/mi
20K· 12.43 mi
1:21:48
Rank: #4025 (-162)
15K → 20K
20:58 | 6:45/mi
Half· 13.11 mi
1:26:19
Rank: #4037 (-12)
20K → Half
4:31 | 6:37/mi
25K· 15.53 mi
1:43:12
Rank: #4308 (-271)
Half → 25K
16:53 | 6:58/mi
30K· 18.64 mi
2:08:19
Rank: #5846 (-1538)
25K → 30K
25:07 | 8:05/mi
20M
2:18:09
Rank: #5783 (+63)
30K → 20M
9:50 | 7:14/mi
21M
2:25:38
Rank: #5669 (+114)
20M → 21M
7:29 | 7:29/mi
35K· 21.75 mi
2:31:53
Rank: #5921 (-252)
21M → 35K
6:15 | 8:21/mi
23M
2:41:29
Rank: #5936 (-15)
35K → 23M
9:36 | 7:40/mi
24M
2:48:45
Rank: #5888 (+48)
23M → 24M
7:16 | 7:16/mi
40K· 24.85 mi
2:55:06
Rank: #5856 (+32)
24M → 40K
6:21 | 7:26/mi
25.2M
2:57:49
Rank: #5814 (+42)
40K → 25.2M
2:43 | 7:53/mi
Finish· 26.22 mi
3:04:50
Rank: #5714 (+100)
25.2M → Finish
7:01 | 6:53/mi

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time1:26:19
Pace6:35 /mi
2nd Half
Distance13.11 mi
Time1:38:31
Pace7:31 /mi
📊Positive Split: 14.1% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi10:24:1520:176:3220:17
6:32
-
10K
6.21 mi10:44:3740:396:3320:22
6:33
+0:01
15K
9.32 mi11:04:481:00:506:3220:11
6:30
-0:03
20K
12.43 mi11:25:461:21:486:3520:58
6:45
+0:15
Half
13.11 mi11:30:171:26:196:354:31
6:37
-0:08
25K
15.53 mi11:47:101:43:126:3916:53
6:58
+0:21
30K
18.64 mi12:12:172:08:196:5325:07
8:05
+1:07
20M
20.00 mi12:22:072:18:096:549:50
7:14
-0:51
21M
21.00 mi12:29:362:25:386:567:29
7:29
+0:15
35K
21.75 mi12:35:512:31:536:596:15
8:21
+0:52
23M
23.00 mi12:45:272:41:297:019:36
7:40
-0:41
24M
24.00 mi12:52:432:48:457:027:16
7:16
-0:24
40K
24.85 mi12:59:042:55:067:036:21
7:26
+0:10
25.2M
25.20 mi13:01:472:57:497:032:43
7:53
+0:27
Finish
26.22 mi13:08:483:04:507:037:01
6:53
-1:00

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

6:30 /mi

Average Pace

7:03 /mi

Slowest Pace

8:21 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

1:33:20

50% of race

Time at Steady Pace

47:49

26% of race

Time at Slower Pace

43:41

24% of race

Average Pace: 7:03 /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 mi10:24:1520:176:3220:17
6:32
#4045
10K
6.21 mi10:44:3740:396:3320:22
6:33
#4077
15K
9.32 mi11:04:481:00:506:3220:11
6:30
#3863
20K
12.43 mi11:25:461:21:486:3520:58
6:45
#4025
Half
13.11 mi11:30:171:26:196:354:31
6:37
#4037
25K
15.53 mi11:47:101:43:126:3916:53
6:58
#4308
30K
18.64 mi12:12:172:08:196:5325:07
8:05
#5846
20M
20.00 mi12:22:072:18:096:549:50
7:14
#5783
21M
21.00 mi12:29:362:25:386:567:29
7:29
#5669
35K
21.75 mi12:35:512:31:536:596:15
8:21
#5921
23M
23.00 mi12:45:272:41:297:019:36
7:40
#5936
24M
24.00 mi12:52:432:48:457:027:16
7:16
#5888
40K
24.85 mi12:59:042:55:067:036:21
7:26
#5856
25.2M
25.20 mi13:01:472:57:497:032:43
7:53
#5814
Finish
26.22 mi13:08:483:04:507:037:01
6:53
#5714
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallMalesM18-39Seg. OverallSeg. MalesSeg. M18-39
5K3.11 mi3.11 mi4045381538153548(Top 12%)3355(Top 21%)3355(Top 59%)
10K6.21 mi3.10 mi4077-323844-293844-294110(Top 14%)3864(Top 24%)3864(Top 68%)
15K9.32 mi3.11 mi3863+2143647+1973647+1973548(Top 12%)3355(Top 21%)3355(Top 59%)
20K12.43 mi3.11 mi4025-1623790-1433790-1434828(Top 17%)4467(Top 28%)4467(Top 79%)
Half13.11 mi0.68 mi4037-123799-93799-94569(Top 16%)4262(Top 26%)4262(Top 76%)
25K15.53 mi2.42 mi4308-2714040-2414040-2416056(Top 21%)5441(Top 34%)5441(Top 96%)
30K18.64 mi3.11 mi5846-15385320-12805320-128011967(Top 42%)8654(Top 54%)8654(Top 153%)
20M20.00 mi1.36 mi5783+635256+645256+645385(Top 19%)4760(Top 30%)4760(Top 84%)
21M21.00 mi1.00 mi5669+1145156+1005156+1004523(Top 16%)4013(Top 25%)4013(Top 71%)
35K21.75 mi0.75 mi5921-2525338-1825338-18214557(Top 51%)9511(Top 59%)9511(Top 169%)
23M23.00 mi1.25 mi5936-155331+75331+77650(Top 27%)5952(Top 37%)5952(Top 105%)
24M24.00 mi1.00 mi5888+485278+535278+536196(Top 22%)5028(Top 31%)5028(Top 89%)
40K24.85 mi0.85 mi5856+325237+415237+416334(Top 22%)5043(Top 31%)5043(Top 89%)
25.2M25.20 mi0.35 mi5814+425198+395198+395232(Top 18%)4253(Top 26%)4253(Top 75%)
Finish26.22 mi1.02 mi5714+1005104+945104+944969(Top 17%)4084(Top 25%)4084(Top 72%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 12%
×21stories
+97ft-345ft

Overall

3548

Males

3355

M18-39

3355

5K→10K

3.1 - 6.2 mi

Top 14%
×5stories
+79ft-138ft

Overall

4110

Males

3864

M18-39

3864

10K→15K

6.2 - 9.3 mi

Top 12%
×3stories
+67ft-78ft

Overall

3548

Males

3355

M18-39

3355

15K→20K

9.3 - 12.4 mi

Top 17%
×5stories
+106ft-86ft

Overall

4828

Males

4467

M18-39

4467

20K→Half

12.4 - 13.1 mi

Top 16%
×2stories
+19ft-37ft

Overall

4569

Males

4262

M18-39

4262

Half→25K

13.1 - 15.5 mi

Top 21%
×4stories
+66ft-88ft

Overall

6056

Males

5441

M18-39

5441

25K→30K

15.5 - 18.6 mi

Top 42%
×9stories
+181ft-148ft

Overall

11967

Males

8654

M18-39

8654

30K→20M

18.6 - 20.0 mi

Top 19%
×5stories
+64ft-50ft

Overall

5385

Males

4760

M18-39

4760

20M→21M

20.0 - 21.0 mi

Top 16%
×8stories
+106ft-24ft

Overall

4523

Males

4013

M18-39

4013

21M→35K

21.0 - 21.8 mi

Top 51%
×7stories
+17ft-86ft

Overall

14557

Males

9511

M18-39

9511

35K→23M

21.8 - 23.0 mi

Top 27%
×5stories
+23ft-63ft

Overall

7650

Males

5952

M18-39

5952

23M→24M

23.0 - 24.0 mi

Top 22%
×6stories
+12ft-82ft

Overall

6196

Males

5028

M18-39

5028

24M→40K

24.0 - 24.9 mi

Top 22%
×1story
+6ft-20ft

Overall

6334

Males

5043

M18-39

5043

40K→25.2M

24.9 - 25.2 mi

Top 18%
×1story
+13ft-16ft

Overall

5232

Males

4253

M18-39

4253

25.2M→Finish

25.2 - 26.2 mi

Top 17%
×2stories
+22ft-21ft

Overall

4969

Males

4084

M18-39

4084

Passing Analysis

Category:
Athletes Passed
1119
Passed By
2788
Net Change
-1669
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#4045
5K → 10K144176-32#4045#4077
10K → 15K23319+214#4077#3863
15K → 20K54216-162#3863#4025
20K → Half1022-12#4025#4037
Half → 25K26297-271#4037#4308
25K → 30K191557-1538#4308#5846
30K → 20M10138+63#5846#5783
20M → 21M12713+114#5783#5669
21M → 35K8260-252#5669#5921
35K → 23M7994-15#5921#5936
23M → 24M7931+48#5936#5888
24M → 40K7139+32#5888#5856
40K → 25.2M5311+42#5856#5814
25.2M → Finish11515+100#5814#5714
TOTALS11192788-1669
📊

Passing Visuals

Category:

📈Position Graph

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🎨Heatmap Timeline

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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