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BOSTON MARATHON 2025

Kerri Mast

Bib: 21094•F

NC

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 (F45-49)
#0 / 1813
Top 35%
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
8:00/mi
24:50
↑ 97↓ 3451.5%
10K· 6.21 mi
7:51/mi
49:14
↑ 79↓ 1380.4%
15K· 9.32 mi
8:00/mi
1:14:04
↑ 67↓ 78
20K· 12.43 mi
7:57/mi
1:38:46
↑ 106↓ 860.1%
Half· 13.11 mi
8:02/mi
1:44:15
↑ 19↓ 370.5%
25K· 15.53 mi
8:28/mi
2:04:47
↑ 66↓ 880.2%
30K· 18.64 mi
8:36/mi
2:31:29
↑ 181↓ 1480.2%
20M
8:54/mi
2:43:34
↑ 64↓ 500.2%
21M
9:26/mi
2:53:00
↑ 106↓ 241.6%
35K· 21.75 mi
8:25/mi
2:59:18
↑ 17↓ 861.7%
23M
9:01/mi
3:10:35
↑ 23↓ 630.6%
24M
8:46/mi
3:19:21
↓ 821.3%
40K· 24.85 mi
9:02/mi
3:27:04
↓ 200.3%
25.2M
9:54/mi
3:30:29
↑ 13↓ 160.2%
Finish· 26.22 mi
8:20/mi
3:38:59
↑ 22↓ 21

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time1:44:15
Pace7:57 /mi
2nd Half
Distance13.11 mi
Time1:54:44
Pace8:45 /mi
📊Positive Split: 10.1% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi11:17:5424:508:0024:50
8:00
-
10K
6.21 mi11:42:1849:147:5524:24
7:51
-0:09
15K
9.32 mi12:07:081:14:047:5724:50
8:00
+0:09
20K
12.43 mi12:31:501:38:467:5724:42
7:57
-0:03
Half
13.11 mi12:37:191:44:157:575:29
8:02
+0:05
25K
15.53 mi12:57:512:04:478:0220:32
8:28
+0:26
30K
18.64 mi13:24:332:31:298:0826:42
8:36
+0:08
20M
20.00 mi13:36:382:43:348:1112:05
8:54
+0:18
21M
21.00 mi13:46:042:53:008:149:26
9:26
+0:32
35K
21.75 mi13:52:222:59:188:156:18
8:25
-1:01
23M
23.00 mi14:03:393:10:358:1711:17
9:01
+0:36
24M
24.00 mi14:12:253:19:218:188:46
8:46
-0:15
40K
24.85 mi14:20:083:27:048:207:43
9:02
+0:16
25.2M
25.20 mi14:23:333:30:298:213:25
9:54
+0:52
Finish
26.22 mi14:32:033:38:598:218:30
8:20
-1:34

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

7:51 /mi

Average Pace

8:21 /mi

Slowest Pace

9:54 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

1:44:15

48% of race

Time at Steady Pace

1:02:02

28% of race

Time at Slower Pace

52:42

24% 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 mi11:17:5424:508:0024:50
8:00
#16540
10K
6.21 mi11:42:1849:147:5524:24
7:51
#15899
15K
9.32 mi12:07:081:14:047:5724:50
8:00
#15893
20K
12.43 mi12:31:501:38:467:5724:42
7:57
#15531
Half
13.11 mi12:37:191:44:157:575:29
8:02
#15564
25K
15.53 mi12:57:512:04:478:0220:32
8:28
#15831
30K
18.64 mi13:24:332:31:298:0826:42
8:36
#15716
20M
20.00 mi13:36:382:43:348:1112:05
8:54
#15689
21M
21.00 mi13:46:042:53:008:149:26
9:26
#15676
35K
21.75 mi13:52:222:59:188:156:18
8:25
#15620
23M
23.00 mi14:03:393:10:358:1711:17
9:01
#15631
24M
24.00 mi14:12:253:19:218:188:46
8:46
#15615
40K
24.85 mi14:20:083:27:048:207:43
9:02
#15624
25.2M
25.20 mi14:23:333:30:298:213:25
9:54
#15634
Finish
26.22 mi14:32:033:38:598:218:30
8:20
#15606
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallFemalesF45-49Seg. OverallSeg. FemalesSeg. F45-49
5K3.11 mi3.11 mi165405476547616013(Top 56%)5152(Top 42%)5152(Top 284%)
10K6.21 mi3.10 mi15899+6415075+4015075+40115310(Top 54%)4730(Top 39%)4730(Top 261%)
15K9.32 mi3.11 mi15893+65079-45079-416013(Top 56%)5152(Top 42%)5152(Top 284%)
20K12.43 mi3.11 mi15531+3624884+1954884+19514558(Top 51%)4401(Top 36%)4401(Top 243%)
Half13.11 mi0.68 mi15564-334905-214905-2116239(Top 57%)5326(Top 44%)5326(Top 294%)
25K15.53 mi2.42 mi15831-2675071-1665071-16616988(Top 60%)5844(Top 48%)5844(Top 322%)
30K18.64 mi3.11 mi15716+1155063+85063+815360(Top 54%)5106(Top 42%)5106(Top 282%)
20M20.00 mi1.36 mi15689+275093-305093-3016188(Top 57%)5707(Top 47%)5707(Top 315%)
21M21.00 mi1.00 mi15676+135124-315124-3115796(Top 56%)5599(Top 46%)5599(Top 309%)
35K21.75 mi0.75 mi15620+565104+205104+2015024(Top 53%)5241(Top 43%)5241(Top 289%)
23M23.00 mi1.25 mi15631-115148-445148-4416335(Top 58%)6072(Top 50%)6072(Top 335%)
24M24.00 mi1.00 mi15615+165161-135161-1316134(Top 57%)6003(Top 49%)6003(Top 331%)
40K24.85 mi0.85 mi15624-95196-355196-3516462(Top 58%)6285(Top 51%)6285(Top 347%)
25.2M25.20 mi0.35 mi15634-105210-145210-1416618(Top 59%)6386(Top 52%)6386(Top 352%)
Finish26.22 mi1.02 mi15606+285215-55215-515215(Top 54%)5600(Top 46%)5600(Top 309%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 56%
×21story building
+97ft-345ft

Overall

16013

Females

5152

F45-49

5152

5K→10K

3.1 - 6.2 mi

Top 54%
×5story building
+79ft-138ft

Overall

15310

Females

4730

F45-49

4730

10K→15K

6.2 - 9.3 mi

Top 56%
×3story building
+67ft-78ft

Overall

16013

Females

5152

F45-49

5152

15K→20K

9.3 - 12.4 mi

Top 51%
×5story building
+106ft-86ft

Overall

14558

Females

4401

F45-49

4401

20K→Half

12.4 - 13.1 mi

Top 57%
×2story building
+19ft-37ft

Overall

16239

Females

5326

F45-49

5326

Half→25K

13.1 - 15.5 mi

Top 60%
×4story building
+66ft-88ft

Overall

16988

Females

5844

F45-49

5844

25K→30K

15.5 - 18.6 mi

Top 54%
×9story building
+181ft-148ft

Overall

15360

Females

5106

F45-49

5106

30K→20M

18.6 - 20.0 mi

Top 57%
×5story building
+64ft-50ft

Overall

16188

Females

5707

F45-49

5707

20M→21M

20.0 - 21.0 mi

Top 56%
×8story building
+106ft-24ft

Overall

15796

Females

5599

F45-49

5599

21M→35K

21.0 - 21.8 mi

Top 53%
×7story building
+17ft-86ft

Overall

15024

Females

5241

F45-49

5241

35K→23M

21.8 - 23.0 mi

Top 58%
×5story building
+23ft-63ft

Overall

16335

Females

6072

F45-49

6072

23M→24M

23.0 - 24.0 mi

Top 57%
×6story building
+12ft-82ft

Overall

16134

Females

6003

F45-49

6003

24M→40K

24.0 - 24.9 mi

Top 58%
×1story
+6ft-20ft

Overall

16462

Females

6285

F45-49

6285

40K→25.2M

24.9 - 25.2 mi

Top 59%
×1story
+13ft-16ft

Overall

16618

Females

6386

F45-49

6386

25.2M→Finish

25.2 - 26.2 mi

Top 54%
×2story building
+22ft-21ft

Overall

15215

Females

5600

F45-49

5600

Passing Analysis

Category:
Athletes Passed
2464
Passed By
1530
Net Change
+934
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#16540
5K → 10K73392+641#16540#15899
10K → 15K205199+6#15899#15893
15K → 20K41351+362#15893#15531
20K → Half2861-33#15531#15564
Half → 25K108375-267#15564#15831
25K → 30K279164+115#15831#15716
30K → 20M143116+27#15716#15689
20M → 21M127114+13#15689#15676
21M → 35K8024+56#15676#15620
35K → 23M102113-11#15620#15631
23M → 24M7357+16#15631#15615
24M → 40K7382-9#15615#15624
40K → 25.2M2232-10#15624#15634
25.2M → Finish7850+28#15634#15606
TOTALS24641530+934
📊

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