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BOSTON MARATHON 2025

Natacha Kozmann

Bib: 11457•F

NY

0:00
0:00
/ mi
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Overall
#0 / 28404
Top 35%
Gender (Female)
#0 / 12228
Top 18%
Division (F18-39)
#0 / 5469
Top 31%
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
7:19/mi
22:45
↑ 97↓ 3451.5%
10K· 6.21 mi
7:14/mi
45:13
↑ 79↓ 1380.4%
15K· 9.32 mi
7:17/mi
1:07:50
↑ 67↓ 78
20K· 12.43 mi
7:17/mi
1:30:27
↑ 106↓ 860.1%
Half· 13.11 mi
7:02/mi
1:35:15
↑ 19↓ 370.5%
25K· 15.53 mi
7:22/mi
1:53:06
↑ 66↓ 880.2%
30K· 18.64 mi
7:38/mi
2:16:50
↑ 181↓ 1480.2%
20M
8:00/mi
2:27:42
↑ 64↓ 500.2%
21M
9:38/mi
2:37:20
↑ 106↓ 241.6%
35K· 21.75 mi
7:45/mi
2:43:08
↑ 17↓ 861.7%
23M
8:33/mi
2:53:50
↑ 23↓ 630.6%
24M
7:56/mi
3:01:46
↓ 821.3%
40K· 24.85 mi
8:18/mi
3:08:52
↓ 200.3%
25.2M
8:48/mi
3:11:54
↑ 13↓ 160.2%
Finish· 26.22 mi
7:17/mi
3:19:19
↑ 22↓ 21

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time1:35:15
Pace7:16 /mi
2nd Half
Distance13.11 mi
Time1:44:04
Pace7:56 /mi
📊Positive Split: 9.3% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi10:48:3122:457:1922:45
7:19
-
10K
6.21 mi11:10:5945:137:1722:28
7:14
-0:05
15K
9.32 mi11:33:361:07:507:1722:37
7:17
+0:03
20K
12.43 mi11:56:131:30:277:1722:37
7:17
0:00
Half
13.11 mi12:01:011:35:157:164:48
7:02
-0:15
25K
15.53 mi12:18:521:53:067:1717:51
7:22
+0:20
30K
18.64 mi12:42:362:16:507:2023:44
7:38
+0:16
20M
20.00 mi12:53:282:27:427:2310:52
8:00
+0:22
21M
21.00 mi13:03:062:37:207:309:38
9:38
+1:38
35K
21.75 mi13:08:542:43:087:305:48
7:45
-1:53
23M
23.00 mi13:19:362:53:507:3310:42
8:33
+0:48
24M
24.00 mi13:27:323:01:467:347:56
7:56
-0:37
40K
24.85 mi13:34:383:08:527:367:06
8:18
+0:22
25.2M
25.20 mi13:37:403:11:547:373:02
8:48
+0:30
Finish
26.22 mi13:45:053:19:197:367:25
7:17
-1:31

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

7:02 /mi

Average Pace

7:36 /mi

Slowest Pace

9:38 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

27:16

14% of race

Time at Steady Pace

2:10:43

66% of race

Time at Slower Pace

41:20

21% of race

Average Pace: 7:36 /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 mi10:48:3122:457:1922:45
7:19
#10599
10K
6.21 mi11:10:5945:137:1722:28
7:14
#10161
15K
9.32 mi11:33:361:07:507:1722:37
7:17
#10024
20K
12.43 mi11:56:131:30:277:1722:37
7:17
#9681
Half
13.11 mi12:01:011:35:157:164:48
7:02
#9560
25K
15.53 mi12:18:521:53:067:1717:51
7:22
#9414
30K
18.64 mi12:42:362:16:507:2023:44
7:38
#9212
20M
20.00 mi12:53:282:27:427:2310:52
8:00
#9270
21M
21.00 mi13:03:062:37:207:309:38
9:38
#9737
35K
21.75 mi13:08:542:43:087:305:48
7:45
#9736
23M
23.00 mi13:19:362:53:507:3310:42
8:33
#9998
24M
24.00 mi13:27:323:01:467:347:56
7:56
#10017
40K
24.85 mi13:34:383:08:527:367:06
8:18
#10069
25.2M
25.20 mi13:37:403:11:547:373:02
8:48
#10064
Finish
26.22 mi13:45:053:19:197:367:25
7:17
#9936
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallFemalesF18-39Seg. OverallSeg. FemalesSeg. F18-39
5K3.11 mi3.11 mi10599208920899844(Top 35%)1821(Top 15%)1821(Top 33%)
10K6.21 mi3.10 mi10161+4381889+2001889+2009776(Top 34%)1730(Top 14%)1730(Top 32%)
15K9.32 mi3.11 mi10024+1371852+371852+379844(Top 35%)1821(Top 15%)1821(Top 33%)
20K12.43 mi3.11 mi9681+3431728+1241728+1248899(Top 31%)1483(Top 12%)1483(Top 27%)
Half13.11 mi0.68 mi9560+1211674+541674+547915(Top 28%)1074(Top 9%)1074(Top 20%)
25K15.53 mi2.42 mi9414+1461638+361638+368860(Top 31%)1583(Top 13%)1583(Top 29%)
30K18.64 mi3.11 mi9212+2021603+351603+358761(Top 31%)1731(Top 14%)1731(Top 32%)
20M20.00 mi1.36 mi9270-581660-571660-5710434(Top 37%)2648(Top 22%)2648(Top 48%)
21M21.00 mi1.00 mi9737-4671898-2381898-23816699(Top 59%)6081(Top 50%)6081(Top 111%)
35K21.75 mi0.75 mi9736+11923-251923-2510482(Top 37%)2833(Top 23%)2833(Top 52%)
23M23.00 mi1.25 mi9998-2622110-1872110-18713590(Top 48%)4574(Top 37%)4574(Top 84%)
24M24.00 mi1.00 mi10017-192153-432153-4310779(Top 38%)3178(Top 26%)3178(Top 58%)
40K24.85 mi0.85 mi10069-522209-562209-5612171(Top 43%)3993(Top 33%)3993(Top 73%)
25.2M25.20 mi0.35 mi10064+52226-172226-1710642(Top 37%)3298(Top 27%)3298(Top 60%)
Finish26.22 mi1.02 mi9936+1282189+372189+377656(Top 27%)1928(Top 16%)1928(Top 35%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 35%
×21story building
+97ft-345ft

Overall

9844

Females

1821

F18-39

1821

5K→10K

3.1 - 6.2 mi

Top 34%
×5story building
+79ft-138ft

Overall

9776

Females

1730

F18-39

1730

10K→15K

6.2 - 9.3 mi

Top 35%
×3story building
+67ft-78ft

Overall

9844

Females

1821

F18-39

1821

15K→20K

9.3 - 12.4 mi

Top 31%
×5story building
+106ft-86ft

Overall

8899

Females

1483

F18-39

1483

20K→Half

12.4 - 13.1 mi

Top 28%
×2story building
+19ft-37ft

Overall

7915

Females

1074

F18-39

1074

Half→25K

13.1 - 15.5 mi

Top 31%
×4story building
+66ft-88ft

Overall

8860

Females

1583

F18-39

1583

25K→30K

15.5 - 18.6 mi

Top 31%
×9story building
+181ft-148ft

Overall

8761

Females

1731

F18-39

1731

30K→20M

18.6 - 20.0 mi

Top 37%
×5story building
+64ft-50ft

Overall

10434

Females

2648

F18-39

2648

20M→21M

20.0 - 21.0 mi

Top 59%
×8story building
+106ft-24ft

Overall

16699

Females

6081

F18-39

6081

21M→35K

21.0 - 21.8 mi

Top 37%
×7story building
+17ft-86ft

Overall

10482

Females

2833

F18-39

2833

35K→23M

21.8 - 23.0 mi

Top 48%
×5story building
+23ft-63ft

Overall

13590

Females

4574

F18-39

4574

23M→24M

23.0 - 24.0 mi

Top 38%
×6story building
+12ft-82ft

Overall

10779

Females

3178

F18-39

3178

24M→40K

24.0 - 24.9 mi

Top 43%
×1story
+6ft-20ft

Overall

12171

Females

3993

F18-39

3993

40K→25.2M

24.9 - 25.2 mi

Top 37%
×1story
+13ft-16ft

Overall

10642

Females

3298

F18-39

3298

25.2M→Finish

25.2 - 26.2 mi

Top 27%
×2story building
+22ft-21ft

Overall

7656

Females

1928

F18-39

1928

Passing Analysis

Category:
Athletes Passed
2331*
Passed By
1664
Net Change
+663
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#10599
5K → 10K53092+438#10599#10161
10K → 15K247110+137#10161#10024
15K → 20K372*29+343#10024#9681
20K → Half1254+121#9681#9560
Half → 25K21367+146#9560#9414
25K → 30K315113+202#9414#9212
30K → 20M82140-58#9212#9270
20M → 21M16483-467#9270#9737
21M → 35K6463+1#9737#9736
35K → 23M47308-262#9736#9998
23M → 24M7895-19#9998#10017
24M → 40K62113-52#10017#10069
40K → 25.2M3732+5#10069#10064
25.2M → Finish143*15+128#10064#9936
TOTALS2331*1664+663

* Includes athletes who did not complete a segment (DNF/DNQ).

📊

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