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BOSTON MARATHON 2023

Jonathan Tsai

Bib: 4021•M

MA

0:00
0:00
/ mi
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Overall
#0 / 26622
Top 18%
Gender (Male)
#0 / 15176
Top 28%
Division (M18-39)
#0 / 5285
Race Day Weather
49°/39°F
light intensity drizzle

⏱️ 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
6:47/mi
21:06
↑ 97↓ 3451.5%
10K· 6.21 mi
6:42/mi
41:54
↑ 79↓ 1380.4%
15K· 9.32 mi
6:41/mi
1:02:41
↑ 67↓ 78
20K· 12.43 mi
6:46/mi
1:23:41
↑ 106↓ 860.1%
Half· 13.11 mi
6:40/mi
1:28:14
↑ 19↓ 370.5%
25K· 15.53 mi
6:50/mi
1:44:49
↑ 66↓ 880.2%
30K· 18.64 mi
7:07/mi
2:06:55
↑ 181↓ 1480.2%
20M
7:14/mi
2:16:45
↑ 64↓ 500.2%
21M
7:47/mi
2:24:32
↑ 106↓ 241.6%
35K· 21.75 mi
6:56/mi
2:29:43
↑ 17↓ 861.7%
23M
7:30/mi
2:39:07
↑ 23↓ 630.6%
24M
7:18/mi
2:46:25
↓ 821.3%
40K· 24.85 mi
7:20/mi
2:52:41
↓ 200.3%
25.2M
7:32/mi
2:55:17
↑ 13↓ 160.2%
Finish· 26.22 mi
6:51/mi
3:02:16
↑ 22↓ 21

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time1:28:14
Pace6:44 /mi
2nd Half
Distance13.11 mi
Time1:34:02
Pace7:10 /mi
📊Positive Split: 6.6% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi10:23:2221:066:4721:06
6:47
-
10K
6.21 mi10:44:1041:546:4520:48
6:42
-0:05
15K
9.32 mi11:04:571:02:416:4420:47
6:41
-0:01
20K
12.43 mi11:25:571:23:416:4421:00
6:46
+0:05
Half
13.11 mi11:30:301:28:146:444:33
6:40
-0:06
25K
15.53 mi11:47:051:44:496:4516:35
6:50
+0:10
30K
18.64 mi12:09:112:06:556:4922:06
7:07
+0:17
20M
20.00 mi12:19:012:16:456:509:50
7:14
+0:07
21M
21.00 mi12:26:482:24:326:537:47
7:47
+0:33
35K
21.75 mi12:31:592:29:436:535:11
6:56
-0:51
23M
23.00 mi12:41:232:39:076:559:24
7:30
+0:34
24M
24.00 mi12:48:412:46:256:567:18
7:18
-0:12
40K
24.85 mi12:54:572:52:416:576:16
7:20
+0:02
25.2M
25.20 mi12:57:332:55:176:572:36
7:32
+0:12
Finish
26.22 mi13:04:323:02:166:576:59
6:51
-0:41

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

6:40 /mi

Average Pace

6:57 /mi

Slowest Pace

7:47 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

2:36:13

86% of race

Time at Steady Pace

26:03

14% of race

Time at Slower Pace

0:00

0% of race

Average Pace: 6:57 /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 mi10:23:2221:066:4721:06
6:47
#4595
10K
6.21 mi10:44:1041:546:4520:48
6:42
#4408
15K
9.32 mi11:04:571:02:416:4420:47
6:41
#4270
20K
12.43 mi11:25:571:23:416:4421:00
6:46
#4191
Half
13.11 mi11:30:301:28:146:444:33
6:40
#4186
25K
15.53 mi11:47:051:44:496:4516:35
6:50
#4189
30K
18.64 mi12:09:112:06:556:4922:06
7:07
#4383
20M
20.00 mi12:19:012:16:456:509:50
7:14
#4491
21M
21.00 mi12:26:482:24:326:537:47
7:47
#4605
35K
21.75 mi12:31:592:29:436:535:11
6:56
#4615
23M
23.00 mi12:41:232:39:076:559:24
7:30
#4709
24M
24.00 mi12:48:412:46:256:567:18
7:18
#4764
40K
24.85 mi12:54:572:52:416:576:16
7:20
#4752
25.2M
25.20 mi12:57:332:55:176:572:36
7:32
#4732
Finish
26.22 mi13:04:323:02:166:576:59
6:51
#4675
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallMalesM18-39Seg. OverallSeg. MalesSeg. M18-39
5K3.11 mi3.11 mi4595428342834039(Top 15%)3795(Top 25%)3795(Top 72%)
10K6.21 mi3.10 mi4408+1874127+1564127+1564290(Top 16%)4018(Top 26%)4018(Top 76%)
15K9.32 mi3.11 mi4270+1383999+1283999+1284039(Top 15%)3795(Top 25%)3795(Top 72%)
20K12.43 mi3.11 mi4191+793933+663933+664083(Top 15%)3829(Top 25%)3829(Top 72%)
Half13.11 mi0.68 mi4186+53923+103923+104076(Top 15%)3828(Top 25%)3828(Top 72%)
25K15.53 mi2.42 mi4189-33927-43927-44508(Top 17%)4200(Top 28%)4200(Top 79%)
30K18.64 mi3.11 mi4383-1944098-1714098-1715001(Top 19%)4594(Top 30%)4594(Top 87%)
20M20.00 mi1.36 mi4491-1084189-914189-915279(Top 20%)4754(Top 31%)4754(Top 90%)
21M21.00 mi1.00 mi4605-1144290-1014290-1016060(Top 23%)5229(Top 34%)5229(Top 99%)
35K21.75 mi0.75 mi4615-104298-84298-84911(Top 18%)4417(Top 29%)4417(Top 84%)
23M23.00 mi1.25 mi4709-944377-794377-796428(Top 24%)5450(Top 36%)5450(Top 103%)
24M24.00 mi1.00 mi4764-554422-454422-456332(Top 24%)5295(Top 35%)5295(Top 100%)
40K24.85 mi0.85 mi4752+124402+204402+205608(Top 21%)4755(Top 31%)4755(Top 90%)
25.2M25.20 mi0.35 mi4732+204383+194383+194071(Top 15%)3613(Top 24%)3613(Top 68%)
Finish26.22 mi1.02 mi4675+574325+584325+584360(Top 16%)3818(Top 25%)3818(Top 72%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 15%
×21story building
+97ft-345ft

Overall

4039

Males

3795

M18-39

3795

5K→10K

3.1 - 6.2 mi

Top 16%
×5story building
+79ft-138ft

Overall

4290

Males

4018

M18-39

4018

10K→15K

6.2 - 9.3 mi

Top 15%
×3story building
+67ft-78ft

Overall

4039

Males

3795

M18-39

3795

15K→20K

9.3 - 12.4 mi

Top 15%
×5story building
+106ft-86ft

Overall

4083

Males

3829

M18-39

3829

20K→Half

12.4 - 13.1 mi

Top 15%
×2story building
+19ft-37ft

Overall

4076

Males

3828

M18-39

3828

Half→25K

13.1 - 15.5 mi

Top 17%
×4story building
+66ft-88ft

Overall

4508

Males

4200

M18-39

4200

25K→30K

15.5 - 18.6 mi

Top 19%
×9story building
+181ft-148ft

Overall

5001

Males

4594

M18-39

4594

30K→20M

18.6 - 20.0 mi

Top 20%
×5story building
+64ft-50ft

Overall

5279

Males

4754

M18-39

4754

20M→21M

20.0 - 21.0 mi

Top 23%
×8story building
+106ft-24ft

Overall

6060

Males

5229

M18-39

5229

21M→35K

21.0 - 21.8 mi

Top 18%
×7story building
+17ft-86ft

Overall

4911

Males

4417

M18-39

4417

35K→23M

21.8 - 23.0 mi

Top 24%
×5story building
+23ft-63ft

Overall

6428

Males

5450

M18-39

5450

23M→24M

23.0 - 24.0 mi

Top 24%
×6story building
+12ft-82ft

Overall

6332

Males

5295

M18-39

5295

24M→40K

24.0 - 24.9 mi

Top 21%
×1story
+6ft-20ft

Overall

5608

Males

4755

M18-39

4755

40K→25.2M

24.9 - 25.2 mi

Top 15%
×1story
+13ft-16ft

Overall

4071

Males

3613

M18-39

3613

25.2M→Finish

25.2 - 26.2 mi

Top 16%
×2story building
+22ft-21ft

Overall

4360

Males

3818

M18-39

3818

Passing Analysis

Category:
Athletes Passed
1163
Passed By
1243
Net Change
-80
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#4595
5K → 10K315128+187#4595#4408
10K → 15K20668+138#4408#4270
15K → 20K13455+79#4270#4191
20K → Half2621+5#4191#4186
Half → 25K7881-3#4186#4189
25K → 30K65259-194#4189#4383
30K → 20M37145-108#4383#4491
20M → 21M29143-114#4491#4605
21M → 35K3646-10#4605#4615
35K → 23M46140-94#4615#4709
23M → 24M2681-55#4709#4764
24M → 40K5341+12#4764#4752
40K → 25.2M266+20#4752#4732
25.2M → Finish8629+57#4732#4675
TOTALS11631243-80
📊

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