Boston Marathon logo
BOSTON MARATHON 2025

Chewei Chang

Bib: 3273•M

0:00
0:00
/ mi
Be the first to cheer!
Overall
#0 / 28404
Gender (Male)
#0 / 16105
Division (M18-39)
#0 / 5642
Race Day Weather
50°/40°F
broken clouds

⏱️ Race Timeline

Start
0:00:00
Race begins
5K· 3.11 mi
19:07
Rank: #1639
Start → 5K
19:07 | 6:09/mi
10K· 6.21 mi
38:18
Rank: #1700 (-61)
5K → 10K
19:11 | 6:10/mi
15K· 9.32 mi
57:56
Rank: #1923 (-223)
10K → 15K
19:38 | 6:19/mi
20K· 12.43 mi
1:18:19
Rank: #2273 (-350)
15K → 20K
20:23 | 6:34/mi
Half· 13.11 mi
1:22:49
Rank: #2365 (-92)
20K → Half
4:30 | 6:36/mi
25K· 15.53 mi
1:39:22
Rank: #2725 (-360)
Half → 25K
16:33 | 6:50/mi
30K· 18.64 mi
2:10:30
Rank: #6674 (-3949)
25K → 30K
31:08 | 10:01/mi
20M
2:32:30
Rank: #11289 (-4615)
30K → 20M
22:00 | 16:11/mi
21M
2:42:23
Rank: #11751 (-462)
20M → 21M
9:53 | 9:53/mi
35K· 21.75 mi
2:49:11
Rank: #12062 (-311)
21M → 35K
6:48 | 9:05/mi
23M
3:02:01
Rank: #12868 (-806)
35K → 23M
12:50 | 10:15/mi
24M
3:12:55
Rank: #13709 (-841)
23M → 24M
10:54 | 10:54/mi
40K· 24.85 mi
3:23:51
Rank: #14756 (-1047)
24M → 40K
10:56 | 12:47/mi
25.2M
3:29:14
Rank: #15335 (-579)
40K → 25.2M
5:23 | 15:37/mi
Finish· 26.22 mi
3:40:33
Rank: #16006 (-671)
25.2M → Finish
11:19 | 11:06/mi

The Course

Is this your race?

Claim it — unlock a deeper AI report on this race, free

A personalized Race Performance Report that goes beyond this page — emailed to you, built from your real splits.

Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time1:22:49
Pace6:19 /mi
2nd Half
Distance13.11 mi
Time2:17:44
Pace10:30 /mi
📊Positive Split: 66.3% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi10:20:0219:076:0919:07
6:09
-
10K
6.21 mi10:39:1338:186:1019:11
6:10
+0:01
15K
9.32 mi10:58:5157:566:1319:38
6:19
+0:09
20K
12.43 mi11:19:141:18:196:1820:23
6:34
+0:15
Half
13.11 mi11:23:441:22:496:194:30
6:36
+0:02
25K
15.53 mi11:40:171:39:226:2416:33
6:50
+0:14
30K
18.64 mi12:11:252:10:307:0031:08
10:01
+3:11
20M
20.00 mi12:33:252:32:307:3722:00
16:11
+6:10
21M
21.00 mi12:43:182:42:237:449:53
9:53
-6:18
35K
21.75 mi12:50:062:49:117:476:48
9:05
-0:48
23M
23.00 mi13:02:563:02:017:5512:50
10:15
+1:10
24M
24.00 mi13:13:503:12:558:0210:54
10:54
+0:39
40K
24.85 mi13:24:463:23:518:1210:56
12:47
+1:53
25.2M
25.20 mi13:30:093:29:148:185:23
15:37
+2:50
Finish
26.22 mi13:41:283:40:338:2511:19
11:06
-4:31

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

6:09 /mi

Average Pace

8:25 /mi

Slowest Pace

16:11 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

1:39:22

45% of race

Time at Steady Pace

1:22:52

38% of race

Time at Slower Pace

38:19

17% of race

Average Pace: 8:25 /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 mi10:20:0219:076:0919:07
6:09
#1639
10K
6.21 mi10:39:1338:186:1019:11
6:10
#1700
15K
9.32 mi10:58:5157:566:1319:38
6:19
#1923
20K
12.43 mi11:19:141:18:196:1820:23
6:34
#2273
Half
13.11 mi11:23:441:22:496:194:30
6:36
#2365
25K
15.53 mi11:40:171:39:226:2416:33
6:50
#2725
30K
18.64 mi12:11:252:10:307:0031:08
10:01
#6674
20M
20.00 mi12:33:252:32:307:3722:00
16:11
#11289
21M
21.00 mi12:43:182:42:237:449:53
9:53
#11751
35K
21.75 mi12:50:062:49:117:476:48
9:05
#12062
23M
23.00 mi13:02:563:02:017:5512:50
10:15
#12868
24M
24.00 mi13:13:503:12:558:0210:54
10:54
#13709
40K
24.85 mi13:24:463:23:518:1210:56
12:47
#14756
25.2M
25.20 mi13:30:093:29:148:185:23
15:37
#15335
Finish
26.22 mi13:41:283:40:338:2511:19
11:06
#16006
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallMalesM18-39Seg. OverallSeg. MalesSeg. M18-39
5K3.11 mi3.11 mi1639155715572469(Top 9%)2358(Top 15%)2358(Top 42%)
10K6.21 mi3.10 mi1700-611618-611618-611797(Top 6%)1706(Top 11%)1706(Top 30%)
15K9.32 mi3.11 mi1923-2231829-2111829-2112469(Top 9%)2358(Top 15%)2358(Top 42%)
20K12.43 mi3.11 mi2273-3502172-3432172-3433493(Top 12%)3308(Top 21%)3308(Top 59%)
Half13.11 mi0.68 mi2365-922256-842256-844447(Top 16%)4169(Top 26%)4169(Top 74%)
25K15.53 mi2.42 mi2725-3602600-3442600-3445089(Top 18%)4666(Top 29%)4666(Top 83%)
30K18.64 mi3.11 mi6674-39495963-33635963-336321646(Top 76%)13001(Top 81%)13001(Top 230%)
20M20.00 mi1.36 mi11289-46158600-26378600-263728207(Top 99%)15983(Top 99%)15983(Top 283%)
21M21.00 mi1.00 mi11751-4628787-1878787-18717823(Top 63%)11072(Top 69%)11072(Top 196%)
35K21.75 mi0.75 mi12062-3118903-1168903-11618629(Top 66%)11307(Top 70%)11307(Top 200%)
23M23.00 mi1.25 mi12868-8069244-3419244-34121258(Top 75%)12517(Top 78%)12517(Top 222%)
24M24.00 mi1.00 mi13709-8419578-3349578-33423755(Top 84%)13689(Top 85%)13689(Top 243%)
40K24.85 mi0.85 mi14756-104710020-44210020-44226047(Top 92%)14812(Top 92%)14812(Top 263%)
25.2M25.20 mi0.35 mi15335-57910247-22710247-22727518(Top 97%)15549(Top 97%)15549(Top 276%)
Finish26.22 mi1.02 mi16006-67110530-28310530-28325557(Top 90%)14553(Top 90%)14553(Top 258%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 9%
×21stories
+97ft-345ft

Overall

2469

Males

2358

M18-39

2358

5K→10K

3.1 - 6.2 mi

Top 6%
×5stories
+79ft-138ft

Overall

1797

Males

1706

M18-39

1706

10K→15K

6.2 - 9.3 mi

Top 9%
×3stories
+67ft-78ft

Overall

2469

Males

2358

M18-39

2358

15K→20K

9.3 - 12.4 mi

Top 12%
×5stories
+106ft-86ft

Overall

3493

Males

3308

M18-39

3308

20K→Half

12.4 - 13.1 mi

Top 16%
×2stories
+19ft-37ft

Overall

4447

Males

4169

M18-39

4169

Half→25K

13.1 - 15.5 mi

Top 18%
×4stories
+66ft-88ft

Overall

5089

Males

4666

M18-39

4666

25K→30K

15.5 - 18.6 mi

Top 76%
×9stories
+181ft-148ft

Overall

21646

Males

13001

M18-39

13001

30K→20M

18.6 - 20.0 mi

Top 99%
×5stories
+64ft-50ft

Overall

28207

Males

15983

M18-39

15983

20M→21M

20.0 - 21.0 mi

Top 63%
×8stories
+106ft-24ft

Overall

17823

Males

11072

M18-39

11072

21M→35K

21.0 - 21.8 mi

Top 66%
×7stories
+17ft-86ft

Overall

18629

Males

11307

M18-39

11307

35K→23M

21.8 - 23.0 mi

Top 75%
×5stories
+23ft-63ft

Overall

21258

Males

12517

M18-39

12517

23M→24M

23.0 - 24.0 mi

Top 84%
×6stories
+12ft-82ft

Overall

23755

Males

13689

M18-39

13689

24M→40K

24.0 - 24.9 mi

Top 92%
×1story
+6ft-20ft

Overall

26047

Males

14812

M18-39

14812

40K→25.2M

24.9 - 25.2 mi

Top 97%
×1story
+13ft-16ft

Overall

27518

Males

15549

M18-39

15549

25.2M→Finish

25.2 - 26.2 mi

Top 90%
×2stories
+22ft-21ft

Overall

25557

Males

14553

M18-39

14553

Passing Analysis

Category:
Athletes Passed
168
Passed By
14533
Net Change
-14367
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#1639
5K → 10K56117-61#1639#1700
10K → 15K13236-223#1700#1923
15K → 20K15365-350#1923#2273
20K → Half092-92#2273#2365
Half → 25K13373-360#2365#2725
25K → 30K13950-3949#2725#6674
30K → 20M24615-4615#6674#11289
20M → 21M18480-462#11289#11751
21M → 35K14325-311#11751#12062
35K → 23M21827-806#12062#12868
23M → 24M5846-841#12868#13709
24M → 40K31050-1047#13709#14756
40K → 25.2M2581-579#14756#15335
25.2M → Finish5676-671#15335#16006
TOTALS16814533-14367
📊

Passing Visuals

Category:
Loading...

🔥Passing Intensity

Loading...

🔄Passing Circle

Loading...

🌊Position Flow

Loading...

🏃Race Lanes

Loading...

Upload your GPX file

Supports Garmin, Apple Watch, Polar, Suunto, COROS, Strava, and other apps

.gpx files up to 10MB

Export Track Data

Download your race performance as a GPX or TCX file to import into Strava, Garmin Connect, or other fitness apps.

Questions or issues regarding timing data?

If you notice any discrepancies in your timing data or have questions about your results, our support team can help.

Contact Race Support
Share Feedback

Public Race Data

Boston Athletic Association

Boston Athletic Association

Mika Timing

Mika Timing