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BOSTON MARATHON 2023

Justin Chiu

Bib: 25646•M

MA

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

⏱️ Race Timeline

Start
0:00:00
Race begins
5K· 3.11 mi
28:22
Rank: #20971
Start → 5K
9:08/mi
28:22 split
10K· 6.21 mi
55:31
Rank: #20363 (+608)
5K → 10K
8:44/mi
27:09 split
15K· 9.32 mi
1:22:44
Rank: #20010 (+353)
10K → 15K
8:46/mi
27:13 split
20K· 12.43 mi
1:49:52
Rank: #19536 (+474)
15K → 20K
8:44/mi
27:08 split
Half· 13.11 mi
1:55:46
Rank: #19494 (+42)
20K → Half
8:39/mi
5:54 split
25K· 15.53 mi
2:17:50
Rank: #19473 (+21)
Half → 25K
9:06/mi
22:04 split
30K· 18.64 mi
2:45:43
Rank: #19049 (+424)
25K → 30K
8:58/mi
27:53 split
20M
2:57:33
Rank: #18770 (+279)
30K → 20M
8:42/mi
11:50 split
21M
3:06:45
Rank: #18503 (+267)
20M → 21M
9:12/mi
9:12 split
35K· 21.75 mi
3:13:01
Rank: #18351 (+152)
21M → 35K
8:23/mi
6:16 split
23M
3:23:53
Rank: #18128 (+223)
35K → 23M
8:41/mi
10:52 split
24M
3:32:35
Rank: #18017 (+111)
23M → 24M
8:42/mi
8:42 split
40K· 24.85 mi
3:40:04
Rank: #17914 (+103)
24M → 40K
8:45/mi
7:29 split
25.2M
3:43:19
Rank: #17871 (+43)
40K → 25.2M
9:25/mi
3:15 split
Finish· 26.22 mi
3:51:52
Rank: #17759 (+112)
25.2M → Finish
8:23/mi
8:33 split

The Course

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Half Splits

1st Half· via Half⚖️ Balanced
Distance13.11 mi
Time1:55:46
Pace8:50 /mi
2nd Half⚖️ Balanced
Distance13.11 mi
Time1:56:06
Pace8:51 /mi
📊Even Split: Consistent pacing between halves

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi11:52:3028:229:0828:22
9:08
-
10K
6.21 mi12:19:3955:318:5627:09
8:44
-0:24
15K
9.32 mi12:46:521:22:448:5327:13
8:46
+0:02
20K
12.43 mi13:14:001:49:528:5027:08
8:44
-0:02
Half
13.11 mi13:19:541:55:468:505:54
8:39
-0:05
25K
15.53 mi13:41:582:17:508:5222:04
9:06
+0:27
30K
18.64 mi14:09:512:45:438:5327:53
8:58
-0:08
20M
20.00 mi14:21:412:57:338:5311:50
8:42
-0:16
21M
21.00 mi14:30:533:06:458:549:12
9:12
+0:30
35K
21.75 mi14:37:093:13:018:536:16
8:23
-0:49
23M
23.00 mi14:48:013:23:538:5210:52
8:41
+0:18
24M
24.00 mi14:56:433:32:358:518:42
8:42
+0:01
40K
24.85 mi15:04:123:40:048:517:29
8:45
+0:03
25.2M
25.20 mi15:07:273:43:198:523:15
9:25
+0:40
Finish
26.22 mi15:16:003:51:528:518:33
8:23
-1:02

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

8:23 /mi

Average Pace

8:51 /mi

Slowest Pace

9:25 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

3:48:37

99% of race

Time at Steady Pace

3:15

1% of race

Time at Slower Pace

0:00

0% of race

Average Pace: 8:51 /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 mi11:52:3028:229:0828:22
9:08
#20971
10K
6.21 mi12:19:3955:318:5627:09
8:44
#20363
15K
9.32 mi12:46:521:22:448:5327:13
8:46
#20010
20K
12.43 mi13:14:001:49:528:5027:08
8:44
#19536
Half
13.11 mi13:19:541:55:468:505:54
8:39
#19494
25K
15.53 mi13:41:582:17:508:5222:04
9:06
#19473
30K
18.64 mi14:09:512:45:438:5327:53
8:58
#19049
20M
20.00 mi14:21:412:57:338:5311:50
8:42
#18770
21M
21.00 mi14:30:533:06:458:549:12
9:12
#18503
35K
21.75 mi14:37:093:13:018:536:16
8:23
#18351
23M
23.00 mi14:48:013:23:538:5210:52
8:41
#18128
24M
24.00 mi14:56:433:32:358:518:42
8:42
#18017
40K
24.85 mi15:04:123:40:048:517:29
8:45
#17914
25.2M
25.20 mi15:07:273:43:198:523:15
9:25
#17871
Finish
26.22 mi15:16:003:51:528:518:33
8:23
#17759
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallMalesM18-39Seg. OverallSeg. MalesSeg. M18-39
5K3.11 mi3.11 mi20971125941259419287(Top 72%)12003(Top 79%)12003(Top 227%)
10K6.21 mi3.10 mi20363+60812383+21112383+21119618(Top 74%)12134(Top 80%)12134(Top 230%)
15K9.32 mi3.11 mi20010+35312243+14012243+14019287(Top 72%)12003(Top 79%)12003(Top 227%)
20K12.43 mi3.11 mi19536+47412067+17612067+17618313(Top 69%)11611(Top 77%)11611(Top 220%)
Half13.11 mi0.68 mi19494+4212047+2012047+2018563(Top 70%)11724(Top 77%)11724(Top 222%)
25K15.53 mi2.42 mi19473+2112049-212049-219408(Top 73%)12010(Top 79%)12010(Top 227%)
30K18.64 mi3.11 mi19049+42411863+18611863+18617028(Top 64%)10930(Top 72%)10930(Top 207%)
20M20.00 mi1.36 mi18770+27911731+13211731+13214897(Top 56%)9954(Top 66%)9954(Top 188%)
21M21.00 mi1.00 mi18503+26711603+12811603+12814476(Top 54%)9716(Top 64%)9716(Top 184%)
35K21.75 mi0.75 mi18351+15211525+7811525+7814575(Top 55%)9693(Top 64%)9693(Top 183%)
23M23.00 mi1.25 mi18128+22311420+10511420+10514243(Top 54%)9481(Top 62%)9481(Top 179%)
24M24.00 mi1.00 mi18017+11111356+6411356+6415653(Top 59%)10023(Top 66%)10023(Top 190%)
40K24.85 mi0.85 mi17914+10311310+4611310+4614812(Top 56%)9611(Top 63%)9611(Top 182%)
25.2M25.20 mi0.35 mi17871+4311298+1211298+1214803(Top 56%)9607(Top 63%)9607(Top 182%)
Finish26.22 mi1.02 mi17759+11211231+6711231+6714666(Top 55%)9577(Top 63%)9577(Top 181%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 72%
×21story building
+97ft-345ft

Overall

19287

Males

12003

M18-39

12003

5K→10K

3.1 - 6.2 mi

Top 74%
×5story building
+79ft-138ft

Overall

19618

Males

12134

M18-39

12134

10K→15K

6.2 - 9.3 mi

Top 72%
×3story building
+67ft-78ft

Overall

19287

Males

12003

M18-39

12003

15K→20K

9.3 - 12.4 mi

Top 69%
×5story building
+106ft-86ft

Overall

18313

Males

11611

M18-39

11611

20K→Half

12.4 - 13.1 mi

Top 70%
×2story building
+19ft-37ft

Overall

18563

Males

11724

M18-39

11724

Half→25K

13.1 - 15.5 mi

Top 73%
×4story building
+66ft-88ft

Overall

19408

Males

12010

M18-39

12010

25K→30K

15.5 - 18.6 mi

Top 64%
×9story building
+181ft-148ft

Overall

17028

Males

10930

M18-39

10930

30K→20M

18.6 - 20.0 mi

Top 56%
×5story building
+64ft-50ft

Overall

14897

Males

9954

M18-39

9954

20M→21M

20.0 - 21.0 mi

Top 54%
×8story building
+106ft-24ft

Overall

14476

Males

9716

M18-39

9716

21M→35K

21.0 - 21.8 mi

Top 55%
×7story building
+17ft-86ft

Overall

14575

Males

9693

M18-39

9693

35K→23M

21.8 - 23.0 mi

Top 54%
×5story building
+23ft-63ft

Overall

14243

Males

9481

M18-39

9481

23M→24M

23.0 - 24.0 mi

Top 59%
×6story building
+12ft-82ft

Overall

15653

Males

10023

M18-39

10023

24M→40K

24.0 - 24.9 mi

Top 56%
×1story
+6ft-20ft

Overall

14812

Males

9611

M18-39

9611

40K→25.2M

24.9 - 25.2 mi

Top 56%
×1story
+13ft-16ft

Overall

14803

Males

9607

M18-39

9607

25.2M→Finish

25.2 - 26.2 mi

Top 55%
×2story building
+22ft-21ft

Overall

14666

Males

9577

M18-39

9577

Passing Analysis

Category:
Athletes Passed
3598
Passed By
386
Net Change
+3212
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#20971
5K → 10K712104+608#20971#20363
10K → 15K41764+353#20363#20010
15K → 20K48915+474#20010#19536
20K → Half5614+42#19536#19494
Half → 25K135114+21#19494#19473
25K → 30K44925+424#19473#19049
30K → 20M2812+279#19049#18770
20M → 21M2703+267#18770#18503
21M → 35K1542+152#18503#18351
35K → 23M2252+223#18351#18128
23M → 24M12615+111#18128#18017
24M → 40K11310+103#18017#17914
40K → 25.2M485+43#17914#17871
25.2M → Finish12311+112#17871#17759
TOTALS3598386+3212
📊

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