Boston Marathon logo
BOSTON MARATHON 2023

Shelby Foster

Bib: 14146•F

PA

0:00
0:00
/ mi
Be the first to cheer!
Overall
#0 / 26622
Top 30%
Gender (Female)
#0 / 11423
Top 11%
Division (F18-39)
#0 / 4884
Top 20%
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
7:40/mi
23:49
↑ 97↓ 3451.5%
10K· 6.21 mi
7:31/mi
47:09
↑ 79↓ 1380.4%
15K· 9.32 mi
7:27/mi
1:10:19
↑ 67↓ 78
20K· 12.43 mi
7:28/mi
1:33:32
↑ 106↓ 860.1%
Half· 13.11 mi
7:23/mi
1:38:34
↑ 19↓ 370.5%
25K· 15.53 mi
7:26/mi
1:56:36
↑ 66↓ 880.2%
30K· 18.64 mi
7:29/mi
2:19:51
↑ 181↓ 1480.2%
20M
7:30/mi
2:30:03
↑ 64↓ 500.2%
21M
7:46/mi
2:37:49
↑ 106↓ 241.6%
35K· 21.75 mi
7:14/mi
2:43:14
↑ 17↓ 861.7%
23M
7:23/mi
2:52:29
↑ 23↓ 630.6%
24M
7:07/mi
2:59:36
↓ 821.3%
40K· 24.85 mi
7:14/mi
3:05:47
↓ 200.3%
25.2M
7:35/mi
3:08:24
↑ 13↓ 160.2%
Finish· 26.22 mi
6:57/mi
3:15:29
↑ 22↓ 21

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 Half
Distance13.11 mi
Time1:38:34
Pace7:31 /mi
2nd Half✓ Faster
Distance13.11 mi
Time1:36:55
Pace7:24 /mi
📊Negative Split: 1.7% faster second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi10:53:1623:497:4023:49
7:40
-
10K
6.21 mi11:16:3647:097:3523:20
7:31
-0:09
15K
9.32 mi11:39:461:10:197:3323:10
7:27
-0:04
20K
12.43 mi12:02:591:33:327:3223:13
7:28
+0:01
Half
13.11 mi12:08:011:38:347:315:02
7:23
-0:05
25K
15.53 mi12:26:031:56:367:3018:02
7:26
+0:03
30K
18.64 mi12:49:182:19:517:3023:15
7:29
+0:03
20M
20.00 mi12:59:302:30:037:3010:12
7:30
+0:01
21M
21.00 mi13:07:162:37:497:317:46
7:46
+0:16
35K
21.75 mi13:12:412:43:147:305:25
7:14
-0:32
23M
23.00 mi13:21:562:52:297:309:15
7:23
+0:09
24M
24.00 mi13:29:032:59:367:297:07
7:07
-0:16
40K
24.85 mi13:35:143:05:477:286:11
7:14
+0:07
25.2M
25.20 mi13:37:513:08:247:292:37
7:35
+0:21
Finish
26.22 mi13:44:563:15:297:287:05
6:57
-0:38

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

6:57 /mi

Average Pace

7:28 /mi

Slowest Pace

7:46 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

2:43:54

84% of race

Time at Steady Pace

31:35

16% of race

Time at Slower Pace

0:00

0% of race

Average Pace: 7:27 /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 mi10:53:1623:497:4023:49
7:40
#11156
10K
6.21 mi11:16:3647:097:3523:20
7:31
#10818
15K
9.32 mi11:39:461:10:197:3323:10
7:27
#10444
20K
12.43 mi12:02:591:33:327:3223:13
7:28
#10060
Half
13.11 mi12:08:011:38:347:315:02
7:23
#10006
25K
15.53 mi12:26:031:56:367:3018:02
7:26
#9704
30K
18.64 mi12:49:182:19:517:3023:15
7:29
#9177
20M
20.00 mi12:59:302:30:037:3010:12
7:30
#8975
21M
21.00 mi13:07:162:37:497:317:46
7:46
#8763
35K
21.75 mi13:12:412:43:147:305:25
7:14
#8684
23M
23.00 mi13:21:562:52:297:309:15
7:23
#8471
24M
24.00 mi13:29:032:59:367:297:07
7:07
#8280
40K
24.85 mi13:35:143:05:477:286:11
7:14
#8118
25.2M
25.20 mi13:37:513:08:247:292:37
7:35
#8030
Finish
26.22 mi13:44:563:15:297:287:05
6:57
#7865
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallFemalesF18-39Seg. OverallSeg. FemalesSeg. F18-39
5K3.11 mi3.11 mi11156240324039835(Top 37%)1761(Top 15%)1761(Top 36%)
10K6.21 mi3.10 mi10818+3382230+1732230+17310533(Top 40%)2070(Top 18%)2070(Top 42%)
15K9.32 mi3.11 mi10444+3742035+1952035+1959835(Top 37%)1761(Top 15%)1761(Top 36%)
20K12.43 mi3.11 mi10060+3841857+1781857+1789110(Top 34%)1530(Top 13%)1530(Top 31%)
Half13.11 mi0.68 mi10006+541835+221835+229271(Top 35%)1563(Top 14%)1563(Top 32%)
25K15.53 mi2.42 mi9704+3021727+1081727+1088325(Top 31%)1298(Top 11%)1298(Top 27%)
30K18.64 mi3.11 mi9177+5271555+1721555+1727126(Top 27%)973(Top 9%)973(Top 20%)
20M20.00 mi1.36 mi8975+2021492+631492+636845(Top 26%)970(Top 8%)970(Top 20%)
21M21.00 mi1.00 mi8763+2121429+631429+636035(Top 23%)819(Top 7%)819(Top 17%)
35K21.75 mi0.75 mi8684+791417+121417+126818(Top 26%)1036(Top 9%)1036(Top 21%)
23M23.00 mi1.25 mi8471+2131360+571360+575824(Top 22%)765(Top 7%)765(Top 16%)
24M24.00 mi1.00 mi8280+1911311+491311+495322(Top 20%)666(Top 6%)666(Top 14%)
40K24.85 mi0.85 mi8118+1621268+431268+435098(Top 19%)691(Top 6%)691(Top 14%)
25.2M25.20 mi0.35 mi8030+881245+231245+234414(Top 17%)569(Top 5%)569(Top 12%)
Finish26.22 mi1.02 mi7865+1651204+411204+414957(Top 19%)717(Top 6%)717(Top 15%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 37%
×21story building
+97ft-345ft

Overall

9835

Females

1761

F18-39

1761

5K→10K

3.1 - 6.2 mi

Top 40%
×5story building
+79ft-138ft

Overall

10533

Females

2070

F18-39

2070

10K→15K

6.2 - 9.3 mi

Top 37%
×3story building
+67ft-78ft

Overall

9835

Females

1761

F18-39

1761

15K→20K

9.3 - 12.4 mi

Top 34%
×5story building
+106ft-86ft

Overall

9110

Females

1530

F18-39

1530

20K→Half

12.4 - 13.1 mi

Top 35%
×2story building
+19ft-37ft

Overall

9271

Females

1563

F18-39

1563

Half→25K

13.1 - 15.5 mi

Top 31%
×4story building
+66ft-88ft

Overall

8325

Females

1298

F18-39

1298

25K→30K

15.5 - 18.6 mi

Top 27%
×9story building
+181ft-148ft

Overall

7126

Females

973

F18-39

973

30K→20M

18.6 - 20.0 mi

Top 26%
×5story building
+64ft-50ft

Overall

6845

Females

970

F18-39

970

20M→21M

20.0 - 21.0 mi

Top 23%
×8story building
+106ft-24ft

Overall

6035

Females

819

F18-39

819

21M→35K

21.0 - 21.8 mi

Top 26%
×7story building
+17ft-86ft

Overall

6818

Females

1036

F18-39

1036

35K→23M

21.8 - 23.0 mi

Top 22%
×5story building
+23ft-63ft

Overall

5824

Females

765

F18-39

765

23M→24M

23.0 - 24.0 mi

Top 20%
×6story building
+12ft-82ft

Overall

5322

Females

666

F18-39

666

24M→40K

24.0 - 24.9 mi

Top 19%
×1story
+6ft-20ft

Overall

5098

Females

691

F18-39

691

40K→25.2M

24.9 - 25.2 mi

Top 17%
×1story
+13ft-16ft

Overall

4414

Females

569

F18-39

569

25.2M→Finish

25.2 - 26.2 mi

Top 19%
×2story building
+22ft-21ft

Overall

4957

Females

717

F18-39

717

Passing Analysis

Category:
Athletes Passed
3598*
Passed By
307
Net Change
+3291
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#11156
5K → 10K499161+338#11156#10818
10K → 15K43460+374#10818#10444
15K → 20K404*20+384#10444#10060
20K → Half639+54#10060#10006
Half → 25K307*5+302#10006#9704
25K → 30K536*9+527#9704#9177
30K → 20M2097+202#9177#8975
20M → 21M2197+212#8975#8763
21M → 35K845+79#8763#8684
35K → 23M2229+213#8684#8471
23M → 24M1932+191#8471#8280
24M → 40K1686+162#8280#8118
40K → 25.2M891+88#8118#8030
25.2M → Finish1716+165#8030#7865
TOTALS3598*307+3291

* Includes athletes who did not complete a segment (DNF/DNQ).

📊

Passing Visuals

Category:
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

Public Race Data

Boston Athletic Association

Boston Athletic Association

Mika Timing

Mika Timing