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BOSTON MARATHON 2025

Kwok Chu Lau

Bib: 18702•F

0:00
0:00
/ mi
Masters
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Overall
#0 / 28404
Gender (Female)
#0 / 12228
Top 43%
Masters (Masters Women)
#0 / 6759
Top 29%
Division (F40-44)
#0 / 1718
Race Day Weather
50°/40°F
broken clouds

⏱️ Race Timeline

Start
0:00:00
Race begins
5K· 3.11 mi
23:50
Rank: #13733
Start → 5K
23:50 | 7:40/mi
10K· 6.21 mi
47:43
Rank: #13753 (-20)
5K → 10K
23:53 | 7:41/mi
15K· 9.32 mi
1:11:56
Rank: #13908 (-155)
10K → 15K
24:13 | 7:48/mi
20K· 12.43 mi
1:36:44
Rank: #14121 (-213)
15K → 20K
24:48 | 7:59/mi
Half· 13.11 mi
1:42:11
Rank: #14211 (-90)
20K → Half
5:27 | 7:59/mi
25K· 15.53 mi
2:03:22
Rank: #15097 (-886)
Half → 25K
21:11 | 8:44/mi
30K· 18.64 mi
2:30:21
Rank: #15256 (-159)
25K → 30K
26:59 | 8:41/mi
20M
2:42:25
Rank: #15296 (-40)
30K → 20M
12:04 | 8:53/mi
21M
2:52:03
Rank: #15348 (-52)
20M → 21M
9:38 | 9:38/mi
35K· 21.75 mi
2:58:33
Rank: #15377 (-29)
21M → 35K
6:30 | 8:41/mi
23M
3:09:44
Rank: #15379 (-2)
35K → 23M
11:11 | 8:56/mi
24M
3:18:27
Rank: #15382 (-3)
23M → 24M
8:43 | 8:43/mi
40K· 24.85 mi
3:26:09
Rank: #15406 (-24)
24M → 40K
7:42 | 9:00/mi
25.2M
3:29:45
Rank: #15453 (-47)
40K → 25.2M
3:36 | 10:26/mi
Finish· 26.22 mi
3:39:04
Rank: #15637 (-184)
25.2M → Finish
9:19 | 9:09/mi

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time1:42:11
Pace7:48 /mi
2nd Half
Distance13.11 mi
Time1:56:53
Pace8:55 /mi
📊Positive Split: 14.4% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi11:14:1323:507:4023:50
7:40
-
10K
6.21 mi11:38:0647:437:4123:53
7:41
+0:01
15K
9.32 mi12:02:191:11:567:4324:13
7:48
+0:07
20K
12.43 mi12:27:071:36:447:4724:48
7:59
+0:11
Half
13.11 mi12:32:341:42:117:485:27
7:59
0:00
25K
15.53 mi12:53:452:03:227:5621:11
8:44
+0:45
30K
18.64 mi13:20:442:30:218:0426:59
8:41
-0:03
20M
20.00 mi13:32:482:42:258:0712:04
8:53
+0:12
21M
21.00 mi13:42:262:52:038:129:38
9:38
+0:45
35K
21.75 mi13:48:562:58:338:136:30
8:41
-0:57
23M
23.00 mi14:00:073:09:448:1511:11
8:56
+0:15
24M
24.00 mi14:08:503:18:278:168:43
8:43
-0:13
40K
24.85 mi14:16:323:26:098:187:42
9:00
+0:17
25.2M
25.20 mi14:20:083:29:458:193:36
10:26
+1:26
Finish
26.22 mi14:29:273:39:048:229:19
9:09
-1:17

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

7:40 /mi

Average Pace

8:22 /mi

Slowest Pace

10:26 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

1:42:11

47% of race

Time at Steady Pace

1:34:20

43% of race

Time at Slower Pace

22:33

10% of race

Average Pace: 8:21 /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 mi11:14:1323:507:4023:50
7:40
#13733
10K
6.21 mi11:38:0647:437:4123:53
7:41
#13753
15K
9.32 mi12:02:191:11:567:4324:13
7:48
#13908
20K
12.43 mi12:27:071:36:447:4724:48
7:59
#14121
Half
13.11 mi12:32:341:42:117:485:27
7:59
#14211
25K
15.53 mi12:53:452:03:227:5621:11
8:44
#15097
30K
18.64 mi13:20:442:30:218:0426:59
8:41
#15256
20M
20.00 mi13:32:482:42:258:0712:04
8:53
#15296
21M
21.00 mi13:42:262:52:038:129:38
9:38
#15348
35K
21.75 mi13:48:562:58:338:136:30
8:41
#15377
23M
23.00 mi14:00:073:09:448:1511:11
8:56
#15379
24M
24.00 mi14:08:503:18:278:168:43
8:43
#15382
40K
24.85 mi14:16:323:26:098:187:42
9:00
#15406
25.2M
25.20 mi14:20:083:29:458:193:36
10:26
#15453
Finish
26.22 mi14:29:273:39:048:229:19
9:09
#15637
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallFemalesF40-44Seg. OverallSeg. FemalesSeg. F40-44
5K3.11 mi3.11 mi137333733373314350(Top 51%)4238(Top 35%)4238(Top 247%)
10K6.21 mi3.10 mi13753-203798-653798-6513796(Top 49%)3839(Top 31%)3839(Top 223%)
15K9.32 mi3.11 mi13908-1553914-1163914-11614350(Top 51%)4238(Top 35%)4238(Top 247%)
20K12.43 mi3.11 mi14121-2134077-1634077-16314814(Top 52%)4544(Top 37%)4544(Top 264%)
Half13.11 mi0.68 mi14211-904131-544131-5415865(Top 56%)5100(Top 42%)5100(Top 297%)
25K15.53 mi2.42 mi15097-8864660-5294660-52918607(Top 66%)6756(Top 55%)6756(Top 393%)
30K18.64 mi3.11 mi15256-1594802-1424802-14215908(Top 56%)5409(Top 44%)5409(Top 315%)
20M20.00 mi1.36 mi15296-404858-564858-5616122(Top 57%)5664(Top 46%)5664(Top 330%)
21M21.00 mi1.00 mi15348-524919-614919-6116708(Top 59%)6090(Top 50%)6090(Top 354%)
35K21.75 mi0.75 mi15377-294959-404959-4016626(Top 59%)6122(Top 50%)6122(Top 356%)
23M23.00 mi1.25 mi15379-25002-435002-4315884(Top 56%)5822(Top 48%)5822(Top 339%)
24M24.00 mi1.00 mi15382-35030-285030-2815848(Top 56%)5838(Top 48%)5838(Top 340%)
40K24.85 mi0.85 mi15406-245072-425072-4216350(Top 58%)6227(Top 51%)6227(Top 362%)
25.2M25.20 mi0.35 mi15453-475113-415113-4118806(Top 66%)7517(Top 61%)7517(Top 438%)
Finish26.22 mi1.02 mi15637-1845234-1215234-12119707(Top 69%)7977(Top 65%)7977(Top 464%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 51%
×21stories
+97ft-345ft

Overall

14350

Females

4238

F40-44

4238

5K→10K

3.1 - 6.2 mi

Top 49%
×5stories
+79ft-138ft

Overall

13796

Females

3839

F40-44

3839

10K→15K

6.2 - 9.3 mi

Top 51%
×3stories
+67ft-78ft

Overall

14350

Females

4238

F40-44

4238

15K→20K

9.3 - 12.4 mi

Top 52%
×5stories
+106ft-86ft

Overall

14814

Females

4544

F40-44

4544

20K→Half

12.4 - 13.1 mi

Top 56%
×2stories
+19ft-37ft

Overall

15865

Females

5100

F40-44

5100

Half→25K

13.1 - 15.5 mi

Top 66%
×4stories
+66ft-88ft

Overall

18607

Females

6756

F40-44

6756

25K→30K

15.5 - 18.6 mi

Top 56%
×9stories
+181ft-148ft

Overall

15908

Females

5409

F40-44

5409

30K→20M

18.6 - 20.0 mi

Top 57%
×5stories
+64ft-50ft

Overall

16122

Females

5664

F40-44

5664

20M→21M

20.0 - 21.0 mi

Top 59%
×8stories
+106ft-24ft

Overall

16708

Females

6090

F40-44

6090

21M→35K

21.0 - 21.8 mi

Top 59%
×7stories
+17ft-86ft

Overall

16626

Females

6122

F40-44

6122

35K→23M

21.8 - 23.0 mi

Top 56%
×5stories
+23ft-63ft

Overall

15884

Females

5822

F40-44

5822

23M→24M

23.0 - 24.0 mi

Top 56%
×6stories
+12ft-82ft

Overall

15848

Females

5838

F40-44

5838

24M→40K

24.0 - 24.9 mi

Top 58%
×1story
+6ft-20ft

Overall

16350

Females

6227

F40-44

6227

40K→25.2M

24.9 - 25.2 mi

Top 66%
×1story
+13ft-16ft

Overall

18806

Females

7517

F40-44

7517

25.2M→Finish

25.2 - 26.2 mi

Top 69%
×2stories
+22ft-21ft

Overall

19707

Females

7977

F40-44

7977

Passing Analysis

Category:
Athletes Passed
1348
Passed By
3252
Net Change
-1904
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#13733
5K → 10K277297-20#13733#13753
10K → 15K131286-155#13753#13908
15K → 20K158371-213#13908#14121
20K → Half797-90#14121#14211
Half → 25K39925-886#14211#15097
25K → 30K201360-159#15097#15256
30K → 20M99139-40#15256#15296
20M → 21M98150-52#15296#15348
21M → 35K5584-29#15348#15377
35K → 23M113115-2#15377#15379
23M → 24M7376-3#15379#15382
24M → 40K6488-24#15382#15406
40K → 25.2M1461-47#15406#15453
25.2M → Finish19203-184#15453#15637
TOTALS13483252-1904
📊

Passing Visuals

Category:
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🔥Passing Intensity

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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