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BOSTON MARATHON 2025

Brynn Castillow

Bib: 12229•F

UT

0:00
0:00
/ mi
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Overall
#0 / 28404
Top 22%
Gender (Female)
#0 / 12228
Top 6%
Division (F18-39)
#0 / 5469
Top 11%
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
7:08/mi
22:11
↑ 97↓ 3451.5%
10K· 6.21 mi
7:06/mi
44:13
↑ 79↓ 1380.4%
15K· 9.32 mi
7:01/mi
1:06:02
↑ 67↓ 78
20K· 12.43 mi
7:06/mi
1:28:05
↑ 106↓ 860.1%
Half· 13.11 mi
6:58/mi
1:32:50
↑ 19↓ 370.5%
25K· 15.53 mi
7:03/mi
1:49:56
↑ 66↓ 880.2%
30K· 18.64 mi
7:09/mi
2:12:09
↑ 181↓ 1480.2%
20M
7:16/mi
2:22:01
↑ 64↓ 500.2%
21M
7:33/mi
2:29:34
↑ 106↓ 241.6%
35K· 21.75 mi
6:50/mi
2:34:41
↑ 17↓ 861.7%
23M
7:06/mi
2:43:35
↑ 23↓ 630.6%
24M
6:54/mi
2:50:29
↓ 821.3%
40K· 24.85 mi
7:06/mi
2:56:33
↓ 200.3%
25.2M
7:53/mi
2:59:16
↑ 13↓ 160.2%
Finish· 26.22 mi
7:10/mi
3:06:34
↑ 22↓ 21

The Course

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Half Splits

1st Half· via Half⚖️ Balanced
Distance13.11 mi
Time1:32:50
Pace7:05 /mi
2nd Half⚖️ Balanced
Distance13.11 mi
Time1:33:44
Pace7:09 /mi
📊Even Split: Consistent pacing between halves

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi10:51:4422:117:0822:11
7:08
-
10K
6.21 mi11:13:4644:137:0722:02
7:06
-0:02
15K
9.32 mi11:35:351:06:027:0521:49
7:01
-0:05
20K
12.43 mi11:57:381:28:057:0522:03
7:06
+0:05
Half
13.11 mi12:02:231:32:507:054:45
6:58
-0:08
25K
15.53 mi12:19:291:49:567:0517:06
7:03
+0:05
30K
18.64 mi12:41:422:12:097:0522:13
7:09
+0:06
20M
20.00 mi12:51:342:22:017:069:52
7:16
+0:07
21M
21.00 mi12:59:072:29:347:077:33
7:33
+0:17
35K
21.75 mi13:04:142:34:417:075:07
6:50
-0:43
23M
23.00 mi13:13:082:43:357:078:54
7:06
+0:16
24M
24.00 mi13:20:022:50:297:066:54
6:54
-0:12
40K
24.85 mi13:26:062:56:337:066:04
7:06
+0:12
25.2M
25.20 mi13:28:492:59:167:072:43
7:53
+0:47
Finish
26.22 mi13:36:073:06:347:077:18
7:10
-0:43

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

6:50 /mi

Average Pace

7:07 /mi

Slowest Pace

7:53 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

2:56:18

94% of race

Time at Steady Pace

10:16

6% of race

Time at Slower Pace

0:00

0% of race

Average Pace: 7:07 /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 mi10:51:4422:117:0822:11
7:08
#8981
10K
6.21 mi11:13:4644:137:0722:02
7:06
#8757
15K
9.32 mi11:35:351:06:027:0521:49
7:01
#8372
20K
12.43 mi11:57:381:28:057:0522:03
7:06
#8090
Half
13.11 mi12:02:231:32:507:054:45
6:58
#8042
25K
15.53 mi12:19:291:49:567:0517:06
7:03
#7767
30K
18.64 mi12:41:422:12:097:0522:13
7:09
#7277
20M
20.00 mi12:51:342:22:017:069:52
7:16
#7075
21M
21.00 mi12:59:072:29:347:077:33
7:33
#6845
35K
21.75 mi13:04:142:34:417:075:07
6:50
#6708
23M
23.00 mi13:13:082:43:357:078:54
7:06
#6495
24M
24.00 mi13:20:022:50:297:066:54
6:54
#6333
40K
24.85 mi13:26:062:56:337:066:04
7:06
#6214
25.2M
25.20 mi13:28:492:59:167:072:43
7:53
#6170
Finish
26.22 mi13:36:073:06:347:077:18
7:10
#6147
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallFemalesF18-39Seg. OverallSeg. FemalesSeg. F18-39
5K3.11 mi3.11 mi8981135713577776(Top 27%)956(Top 8%)956(Top 17%)
10K6.21 mi3.10 mi8757+2241276+811276+818616(Top 30%)1218(Top 10%)1218(Top 22%)
15K9.32 mi3.11 mi8372+3851147+1291147+1297776(Top 27%)956(Top 8%)956(Top 17%)
20K12.43 mi3.11 mi8090+2821054+931054+937502(Top 26%)928(Top 8%)928(Top 17%)
Half13.11 mi0.68 mi8042+481041+131041+137353(Top 26%)851(Top 7%)851(Top 16%)
25K15.53 mi2.42 mi7767+275962+79962+796670(Top 23%)771(Top 6%)771(Top 14%)
30K18.64 mi3.11 mi7277+490854+108854+1085627(Top 20%)581(Top 5%)581(Top 11%)
20M20.00 mi1.36 mi7075+202822+32822+325577(Top 20%)669(Top 5%)669(Top 12%)
21M21.00 mi1.00 mi6845+230787+35787+354896(Top 17%)587(Top 5%)587(Top 11%)
35K21.75 mi0.75 mi6708+137764+23764+234422(Top 16%)481(Top 4%)481(Top 9%)
23M23.00 mi1.25 mi6495+213737+27737+274414(Top 16%)514(Top 4%)514(Top 9%)
24M24.00 mi1.00 mi6333+162712+25712+254126(Top 15%)483(Top 4%)483(Top 9%)
40K24.85 mi0.85 mi6214+119698+14698+144483(Top 16%)630(Top 5%)630(Top 12%)
25.2M25.20 mi0.35 mi6170+44693+5693+55356(Top 19%)986(Top 8%)986(Top 18%)
Finish26.22 mi1.02 mi6147+23711-18711-186826(Top 24%)1571(Top 13%)1571(Top 29%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 27%
×21story building
+97ft-345ft

Overall

7776

Females

956

F18-39

956

5K→10K

3.1 - 6.2 mi

Top 30%
×5story building
+79ft-138ft

Overall

8616

Females

1218

F18-39

1218

10K→15K

6.2 - 9.3 mi

Top 27%
×3story building
+67ft-78ft

Overall

7776

Females

956

F18-39

956

15K→20K

9.3 - 12.4 mi

Top 26%
×5story building
+106ft-86ft

Overall

7502

Females

928

F18-39

928

20K→Half

12.4 - 13.1 mi

Top 26%
×2story building
+19ft-37ft

Overall

7353

Females

851

F18-39

851

Half→25K

13.1 - 15.5 mi

Top 23%
×4story building
+66ft-88ft

Overall

6670

Females

771

F18-39

771

25K→30K

15.5 - 18.6 mi

Top 20%
×9story building
+181ft-148ft

Overall

5627

Females

581

F18-39

581

30K→20M

18.6 - 20.0 mi

Top 20%
×5story building
+64ft-50ft

Overall

5577

Females

669

F18-39

669

20M→21M

20.0 - 21.0 mi

Top 17%
×8story building
+106ft-24ft

Overall

4896

Females

587

F18-39

587

21M→35K

21.0 - 21.8 mi

Top 16%
×7story building
+17ft-86ft

Overall

4422

Females

481

F18-39

481

35K→23M

21.8 - 23.0 mi

Top 16%
×5story building
+23ft-63ft

Overall

4414

Females

514

F18-39

514

23M→24M

23.0 - 24.0 mi

Top 15%
×6story building
+12ft-82ft

Overall

4126

Females

483

F18-39

483

24M→40K

24.0 - 24.9 mi

Top 16%
×1story
+6ft-20ft

Overall

4483

Females

630

F18-39

630

40K→25.2M

24.9 - 25.2 mi

Top 19%
×1story
+13ft-16ft

Overall

5356

Females

986

F18-39

986

25.2M→Finish

25.2 - 26.2 mi

Top 24%
×2story building
+22ft-21ft

Overall

6826

Females

1571

F18-39

1571

Passing Analysis

Category:
Athletes Passed
3135
Passed By
301
Net Change
+2834
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#8981
5K → 10K343119+224#8981#8757
10K → 15K41025+385#8757#8372
15K → 20K31634+282#8372#8090
20K → Half5911+48#8090#8042
Half → 25K28712+275#8042#7767
25K → 30K50010+490#7767#7277
30K → 20M21210+202#7277#7075
20M → 21M2344+230#7075#6845
21M → 35K1370+137#6845#6708
35K → 23M2185+213#6708#6495
23M → 24M1642+162#6495#6333
24M → 40K1223+119#6333#6214
40K → 25.2M5612+44#6214#6170
25.2M → Finish7754+23#6170#6147
TOTALS3135301+2834
📊

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