Boston Marathon logo
BOSTON MARATHON 2025

Sunjung Na

Bib: 20309•F

0:00
0:00
/ mi
Masters
Be the first to cheer!
Overall
#0 / 28404
Gender (Female)
#0 / 12228
Masters (Masters Women)
#0 / 6759
Division (F40-44)
#0 / 1718
Race Day Weather
50°/40°F
broken clouds

⏱️ Race Timeline

Start
0:00:00
Race begins
5K· 3.11 mi
26:59
Rank: #20948
Start → 5K
26:59 | 8:41/mi
10K· 6.21 mi
55:04
Rank: #21770 (-822)
5K → 10K
28:05 | 9:02/mi
15K· 9.32 mi
1:22:13
Rank: #21373 (+397)
10K → 15K
27:09 | 8:44/mi
20K· 12.43 mi
1:50:31
Rank: #21413 (-40)
15K → 20K
28:18 | 9:07/mi
Half· 13.11 mi
1:56:17
Rank: #21273 (+140)
20K → Half
5:46 | 8:27/mi
25K· 15.53 mi
2:17:22
Rank: #20831 (+442)
Half → 25K
21:05 | 8:42/mi
30K· 18.64 mi
2:47:49
Rank: #20884 (-53)
25K → 30K
30:27 | 9:48/mi
20M
3:00:07
Rank: #20588 (+296)
30K → 20M
12:18 | 9:03/mi
21M
3:09:51
Rank: #20395 (+193)
20M → 21M
9:44 | 9:44/mi
35K· 21.75 mi
3:16:40
Rank: #20315 (+80)
21M → 35K
6:49 | 9:07/mi
23M
3:27:55
Rank: #20108 (+207)
35K → 23M
11:15 | 8:59/mi
24M
3:37:09
Rank: #20044 (+64)
23M → 24M
9:14 | 9:14/mi
40K· 24.85 mi
3:44:55
Rank: #19920 (+124)
24M → 40K
7:46 | 9:05/mi
25.2M
3:48:56
Rank: #19980 (-60)
40K → 25.2M
4:01 | 11:39/mi
Finish· 26.22 mi
3:57:36
Rank: #19864 (+116)
25.2M → Finish
8:40 | 8:30/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
Time1:56:17
Pace8:52 /mi
2nd Half
Distance13.11 mi
Time2:01:19
Pace9:15 /mi
📊Positive Split: 4.3% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi11:26:3726:598:4126:59
8:41
-
10K
6.21 mi11:54:4255:048:5228:05
9:02
+0:21
15K
9.32 mi12:21:511:22:138:4927:09
8:44
-0:18
20K
12.43 mi12:50:091:50:318:5428:18
9:07
+0:23
Half
13.11 mi12:55:551:56:178:525:46
8:27
-0:40
25K
15.53 mi13:17:002:17:228:5121:05
8:42
+0:15
30K
18.64 mi13:47:272:47:499:0030:27
9:48
+1:06
20M
20.00 mi13:59:453:00:079:0012:18
9:03
-0:45
21M
21.00 mi14:09:293:09:519:029:44
9:44
+0:41
35K
21.75 mi14:16:183:16:409:036:49
9:07
-0:37
23M
23.00 mi14:27:333:27:559:0211:15
8:59
-0:08
24M
24.00 mi14:36:473:37:099:039:14
9:14
+0:15
40K
24.85 mi14:44:333:44:559:037:46
9:05
-0:09
25.2M
25.20 mi14:48:343:48:569:054:01
11:39
+2:34
Finish
26.22 mi14:57:143:57:369:048:40
8:30
-3:09

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

8:27 /mi

Average Pace

9:04 /mi

Slowest Pace

11:39 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

14:26

6% of race

Time at Steady Pace

2:58:58

75% of race

Time at Slower Pace

44:12

19% of race

Average Pace: 9:04 /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 mi11:26:3726:598:4126:59
8:41
#20948
10K
6.21 mi11:54:4255:048:5228:05
9:02
#21770
15K
9.32 mi12:21:511:22:138:4927:09
8:44
#21373
20K
12.43 mi12:50:091:50:318:5428:18
9:07
#21413
Half
13.11 mi12:55:551:56:178:525:46
8:27
#21273
25K
15.53 mi13:17:002:17:228:5121:05
8:42
#20831
30K
18.64 mi13:47:272:47:499:0030:27
9:48
#20884
20M
20.00 mi13:59:453:00:079:0012:18
9:03
#20588
21M
21.00 mi14:09:293:09:519:029:44
9:44
#20395
35K
21.75 mi14:16:183:16:409:036:49
9:07
#20315
23M
23.00 mi14:27:333:27:559:0211:15
8:59
#20108
24M
24.00 mi14:36:473:37:099:039:14
9:14
#20044
40K
24.85 mi14:44:333:44:559:037:46
9:05
#19920
25.2M
25.20 mi14:48:343:48:569:054:01
11:39
#19980
Finish
26.22 mi14:57:143:57:369:048:40
8:30
#19864
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallFemalesF40-44Seg. OverallSeg. FemalesSeg. F40-44
5K3.11 mi3.11 mi209488050805020698(Top 73%)7828(Top 64%)7828(Top 456%)
10K6.21 mi3.10 mi21770-8228484-4348484-43422550(Top 79%)8891(Top 73%)8891(Top 518%)
15K9.32 mi3.11 mi21373+3978232+2528232+25220698(Top 73%)7828(Top 64%)7828(Top 456%)
20K12.43 mi3.11 mi21413-408269-378269-3721489(Top 76%)8310(Top 68%)8310(Top 484%)
Half13.11 mi0.68 mi21273+1408185+848185+8418966(Top 67%)6889(Top 56%)6889(Top 401%)
25K15.53 mi2.42 mi20831+4427947+2387947+23818380(Top 65%)6645(Top 54%)6645(Top 387%)
30K18.64 mi3.11 mi20884-538027-808027-8021001(Top 74%)8228(Top 67%)8228(Top 479%)
20M20.00 mi1.36 mi20588+2967879+1487879+14817100(Top 60%)6202(Top 51%)6202(Top 361%)
21M21.00 mi1.00 mi20395+1937794+857794+8517213(Top 61%)6385(Top 52%)6385(Top 372%)
35K21.75 mi0.75 mi20315+807770+247770+2418803(Top 66%)7354(Top 60%)7354(Top 428%)
23M23.00 mi1.25 mi20108+2077683+877683+8716204(Top 57%)6006(Top 49%)6006(Top 350%)
24M24.00 mi1.00 mi20044+647665+187665+1818531(Top 65%)7315(Top 60%)7315(Top 426%)
40K24.85 mi0.85 mi19920+1247614+517614+5116817(Top 59%)6497(Top 53%)6497(Top 378%)
25.2M25.20 mi0.35 mi19980-607655-417655-4122448(Top 79%)9371(Top 77%)9371(Top 545%)
Finish26.22 mi1.02 mi19864+1167607+487607+4816296(Top 57%)6200(Top 51%)6200(Top 361%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 73%
×21stories
+97ft-345ft

Overall

20698

Females

7828

F40-44

7828

5K→10K

3.1 - 6.2 mi

Top 79%
×5stories
+79ft-138ft

Overall

22550

Females

8891

F40-44

8891

10K→15K

6.2 - 9.3 mi

Top 73%
×3stories
+67ft-78ft

Overall

20698

Females

7828

F40-44

7828

15K→20K

9.3 - 12.4 mi

Top 76%
×5stories
+106ft-86ft

Overall

21489

Females

8310

F40-44

8310

20K→Half

12.4 - 13.1 mi

Top 67%
×2stories
+19ft-37ft

Overall

18966

Females

6889

F40-44

6889

Half→25K

13.1 - 15.5 mi

Top 65%
×4stories
+66ft-88ft

Overall

18380

Females

6645

F40-44

6645

25K→30K

15.5 - 18.6 mi

Top 74%
×9stories
+181ft-148ft

Overall

21001

Females

8228

F40-44

8228

30K→20M

18.6 - 20.0 mi

Top 60%
×5stories
+64ft-50ft

Overall

17100

Females

6202

F40-44

6202

20M→21M

20.0 - 21.0 mi

Top 61%
×8stories
+106ft-24ft

Overall

17213

Females

6385

F40-44

6385

21M→35K

21.0 - 21.8 mi

Top 66%
×7stories
+17ft-86ft

Overall

18803

Females

7354

F40-44

7354

35K→23M

21.8 - 23.0 mi

Top 57%
×5stories
+23ft-63ft

Overall

16204

Females

6006

F40-44

6006

23M→24M

23.0 - 24.0 mi

Top 65%
×6stories
+12ft-82ft

Overall

18531

Females

7315

F40-44

7315

24M→40K

24.0 - 24.9 mi

Top 59%
×1story
+6ft-20ft

Overall

16817

Females

6497

F40-44

6497

40K→25.2M

24.9 - 25.2 mi

Top 79%
×1story
+13ft-16ft

Overall

22448

Females

9371

F40-44

9371

25.2M→Finish

25.2 - 26.2 mi

Top 57%
×2stories
+22ft-21ft

Overall

16296

Females

6200

F40-44

6200

Passing Analysis

Category:
Athletes Passed
2695
Passed By
1611
Net Change
+1084
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#20948
5K → 10K66888-822#20948#21770
10K → 15K46366+397#21770#21373
15K → 20K189229-40#21373#21413
20K → Half1444+140#21413#21273
Half → 25K4442+442#21273#20831
25K → 30K197250-53#20831#20884
30K → 20M3015+296#20884#20588
20M → 21M20512+193#20588#20395
21M → 35K9818+80#20395#20315
35K → 23M2114+207#20315#20108
23M → 24M9733+64#20108#20044
24M → 40K13410+124#20044#19920
40K → 25.2M1171-60#19920#19980
25.2M → Finish13519+116#19980#19864
TOTALS26951611+1084
📊

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