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BOSTON MARATHON 2023

Kung-Chi Chang

Bib: 4509•M

MA

0:00
0:00
/ mi
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Overall
#0 / 26622
Top 9%
Gender (Male)
#0 / 15176
Top 15%
Division (M18-39)
#0 / 5285
Top 34%
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
6:50/mi
21:14
↑ 97↓ 3451.5%
10K· 6.21 mi
6:37/mi
41:48
↑ 79↓ 1380.4%
15K· 9.32 mi
6:33/mi
1:02:09
↑ 67↓ 78
20K· 12.43 mi
6:37/mi
1:22:42
↑ 106↓ 860.1%
Half· 13.11 mi
6:30/mi
1:27:08
↑ 19↓ 370.5%
25K· 15.53 mi
6:35/mi
1:43:06
↑ 66↓ 880.2%
30K· 18.64 mi
6:39/mi
2:03:46
↑ 181↓ 1480.2%
20M
6:34/mi
2:12:42
↑ 64↓ 500.2%
21M
7:05/mi
2:19:47
↑ 106↓ 241.6%
35K· 21.75 mi
6:25/mi
2:24:35
↑ 17↓ 861.7%
23M
6:32/mi
2:32:46
↑ 23↓ 630.6%
24M
6:23/mi
2:39:09
↓ 821.3%
40K· 24.85 mi
6:36/mi
2:44:48
↓ 200.3%
25.2M
6:58/mi
2:47:12
↑ 13↓ 160.2%
Finish· 26.22 mi
6:25/mi
2:53:44
↑ 22↓ 21

The Course

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Half Splits

1st Half· via Half⚖️ Balanced
Distance13.11 mi
Time1:27:08
Pace6:39 /mi
2nd Half⚖️ Balanced
Distance13.11 mi
Time1:26:36
Pace6:36 /mi
📊Even Split: Consistent pacing between halves

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi10:23:5821:146:5021:14
6:50
-
10K
6.21 mi10:44:3241:486:4420:34
6:37
-0:13
15K
9.32 mi11:04:531:02:096:4020:21
6:33
-0:04
20K
12.43 mi11:25:261:22:426:3920:33
6:37
+0:04
Half
13.11 mi11:29:521:27:086:394:26
6:30
-0:07
25K
15.53 mi11:45:501:43:066:3815:58
6:35
+0:05
30K
18.64 mi12:06:302:03:466:3820:40
6:39
+0:04
20M
20.00 mi12:15:262:12:426:388:56
6:34
-0:05
21M
21.00 mi12:22:312:19:476:397:05
7:05
+0:31
35K
21.75 mi12:27:192:24:356:394:48
6:25
-0:40
23M
23.00 mi12:35:302:32:466:398:11
6:32
+0:07
24M
24.00 mi12:41:532:39:096:386:23
6:23
-0:09
40K
24.85 mi12:47:322:44:486:385:39
6:36
+0:13
25.2M
25.20 mi12:49:562:47:126:382:24
6:58
+0:22
Finish
26.22 mi12:56:282:53:446:386:32
6:25
-0:33

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

6:23 /mi

Average Pace

6:38 /mi

Slowest Pace

7:05 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

2:46:39

96% of race

Time at Steady Pace

7:05

4% of race

Time at Slower Pace

0:00

0% of race

Average Pace: 6:38 /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 mi10:23:5821:146:5021:14
6:50
#4977
10K
6.21 mi10:44:3241:486:4420:34
6:37
#4236
15K
9.32 mi11:04:531:02:096:4020:21
6:33
#3690
20K
12.43 mi11:25:261:22:426:3920:33
6:37
#3483
Half
13.11 mi11:29:521:27:086:394:26
6:30
#3438
25K
15.53 mi11:45:501:43:066:3815:58
6:35
#3255
30K
18.64 mi12:06:302:03:466:3820:40
6:39
#2970
20M
20.00 mi12:15:262:12:426:388:56
6:34
#2846
21M
21.00 mi12:22:312:19:476:397:05
7:05
#2786
35K
21.75 mi12:27:192:24:356:394:48
6:25
#2734
23M
23.00 mi12:35:302:32:466:398:11
6:32
#2598
24M
24.00 mi12:41:532:39:096:386:23
6:23
#2516
40K
24.85 mi12:47:322:44:486:385:39
6:36
#2470
25.2M
25.20 mi12:49:562:47:126:382:24
6:58
#2443
Finish
26.22 mi12:56:282:53:446:386:32
6:25
#2415
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallMalesM18-39Seg. OverallSeg. MalesSeg. M18-39
5K3.11 mi3.11 mi4977461946192921(Top 11%)2792(Top 18%)2792(Top 53%)
10K6.21 mi3.10 mi4236+7413969+6503969+6503622(Top 14%)3419(Top 23%)3419(Top 65%)
15K9.32 mi3.11 mi3690+5463484+4853484+4852921(Top 11%)2792(Top 18%)2792(Top 53%)
20K12.43 mi3.11 mi3483+2073300+1843300+1842940(Top 11%)2800(Top 18%)2800(Top 53%)
Half13.11 mi0.68 mi3438+453259+413259+412748(Top 10%)2632(Top 17%)2632(Top 50%)
25K15.53 mi2.42 mi3255+1833100+1593100+1592613(Top 10%)2501(Top 16%)2501(Top 47%)
30K18.64 mi3.11 mi2970+2852834+2662834+2662185(Top 8%)2086(Top 14%)2086(Top 39%)
20M20.00 mi1.36 mi2846+1242720+1142720+1141757(Top 7%)1677(Top 11%)1677(Top 32%)
21M21.00 mi1.00 mi2786+602664+562664+562534(Top 10%)2392(Top 16%)2392(Top 45%)
35K21.75 mi0.75 mi2734+522614+502614+502042(Top 8%)1940(Top 13%)1940(Top 37%)
23M23.00 mi1.25 mi2598+1362484+1302484+1301568(Top 6%)1490(Top 10%)1490(Top 28%)
24M24.00 mi1.00 mi2516+822406+782406+781637(Top 6%)1550(Top 10%)1550(Top 29%)
40K24.85 mi0.85 mi2470+462360+462360+461949(Top 7%)1831(Top 12%)1831(Top 35%)
25.2M25.20 mi0.35 mi2443+272333+272333+271637(Top 6%)1543(Top 10%)1543(Top 29%)
Finish26.22 mi1.02 mi2415+282306+272306+272058(Top 8%)1913(Top 13%)1913(Top 36%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 11%
×21story building
+97ft-345ft

Overall

2921

Males

2792

M18-39

2792

5K→10K

3.1 - 6.2 mi

Top 14%
×5story building
+79ft-138ft

Overall

3622

Males

3419

M18-39

3419

10K→15K

6.2 - 9.3 mi

Top 11%
×3story building
+67ft-78ft

Overall

2921

Males

2792

M18-39

2792

15K→20K

9.3 - 12.4 mi

Top 11%
×5story building
+106ft-86ft

Overall

2940

Males

2800

M18-39

2800

20K→Half

12.4 - 13.1 mi

Top 10%
×2story building
+19ft-37ft

Overall

2748

Males

2632

M18-39

2632

Half→25K

13.1 - 15.5 mi

Top 10%
×4story building
+66ft-88ft

Overall

2613

Males

2501

M18-39

2501

25K→30K

15.5 - 18.6 mi

Top 8%
×9story building
+181ft-148ft

Overall

2185

Males

2086

M18-39

2086

30K→20M

18.6 - 20.0 mi

Top 7%
×5story building
+64ft-50ft

Overall

1757

Males

1677

M18-39

1677

20M→21M

20.0 - 21.0 mi

Top 10%
×8story building
+106ft-24ft

Overall

2534

Males

2392

M18-39

2392

21M→35K

21.0 - 21.8 mi

Top 8%
×7story building
+17ft-86ft

Overall

2042

Males

1940

M18-39

1940

35K→23M

21.8 - 23.0 mi

Top 6%
×5story building
+23ft-63ft

Overall

1568

Males

1490

M18-39

1490

23M→24M

23.0 - 24.0 mi

Top 6%
×6story building
+12ft-82ft

Overall

1637

Males

1550

M18-39

1550

24M→40K

24.0 - 24.9 mi

Top 7%
×1story
+6ft-20ft

Overall

1949

Males

1831

M18-39

1831

40K→25.2M

24.9 - 25.2 mi

Top 6%
×1story
+13ft-16ft

Overall

1637

Males

1543

M18-39

1543

25.2M→Finish

25.2 - 26.2 mi

Top 8%
×2story building
+22ft-21ft

Overall

2058

Males

1913

M18-39

1913

Passing Analysis

Category:
Athletes Passed
2681
Passed By
119
Net Change
+2562
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#4977
5K → 10K76322+741#4977#4236
10K → 15K5537+546#4236#3690
15K → 20K22013+207#3690#3483
20K → Half494+45#3483#3438
Half → 25K1929+183#3438#3255
25K → 30K2883+285#3255#2970
30K → 20M1240+124#2970#2846
20M → 21M7212+60#2846#2786
21M → 35K575+52#2786#2734
35K → 23M1393+136#2734#2598
23M → 24M831+82#2598#2516
24M → 40K5610+46#2516#2470
40K → 25.2M314+27#2470#2443
25.2M → Finish5426+28#2443#2415
TOTALS2681119+2562
📊

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