Mackenzie O'Brien

Age: 10 years old
Age Category: 10 & under
Team: Tollefson Swimming | Potomac Valley Swimming

Personal Best

Short course distance

Event

Time

Age

Date

Standard

Next Standard

Tollefson Swimming

Potomac Valley Swimming

Eastern Zone

USA

Free 50 Y

31.74

01/17/2026

AA: 30.89 (+0.85s | 2.7%)

246

1,000+

Free 100 Y

1:13.92

12/11/2025

A: 1:11.49 (+2.43s | 3.3%)

430

1,000+

50 Free

34.27

100 Free

39.65

1:13.92

100 Free

1:13.92

Free 200 Y

2:51.64

09/27/2025

A: 2:38.39 (+13.25s | 7.7%)

145

632

1,000+

50 Free

36.06

100 Free

43.02

1:19.08

100 Free

1:19.08

150 Free

47.42

2:06.50

200 Free

45.14

2:51.64

100 Free

1:32.56

Back 50 Y

38.17

10/10/2025

A: 37.99 (+0.18s | 0.5%)

352

1,000+

Breast 50 Y

39.30

02/01/2026

AAA: 38.89 (+0.41s | 1.0%)

180

Breast 100 Y

1:25.18

10/10/2025

AAA: 1:24.69 (+0.49s | 0.6%)

281

50 Breast

39.27

100 Breast

45.91

1:25.18

100 Breast

1:25.18

Breast 200 Y

3:08.84

10/10/2025

50 Breast

41.17

100 Breast

48.88

1:30.05

100 Breast

1:30.05

150 Breast

48.93

2:18.98

200 Breast

49.86

3:08.84

100 Breast

1:38.79

Fly 50 Y

37.51

01/17/2026

A: 36.99 (+0.52s | 1.4%)

112

373

1,000+

Fly 100 Y

1:34.74

01/17/2026

A: 1:26.09 (+8.65s | 9.1%)

130

489

1,000+

50 Fly

43.66

100 Fly

51.08

1:34.74

100 Fly

1:34.74

IM 100 Y

1:20.68

01/17/2026

AA: 1:18.39 (+2.29s | 2.8%)

206

650

50 IM

39.62

100 IM

41.06

1:20.68

100 IM

1:20.68

IM 200 Y

3:02.16

01/17/2026

A: 2:55.49 (+6.67s | 3.7%)

365

1,000+

50 Fly

41.36

100 Back

48.97

1:30.33

100 IM

1:30.33

150 Breast

49.21

2:19.54

200 Free

42.62

3:02.16

100 IM

1:31.83

Long course distance

Event	Time		Age	Date	Standard	Next Standard	Tollefson Swimming	Potomac Valley Swimming	Eastern Zone	USA

Above are the fastest times that Mackenzie O'Brien has achieved in her swimming career. For each event, you can find Mackenzie's best time, the corresponding time standard, as well as how much faster Mackenzie needs to be to reach the next level. The last columns provide Mackenzie rankings at the team and LSC levels. These rankings are based on the Mackenzie's personal best, her current age category, and team; and are calculated from all the meets results.

Time Standards

Got the currrent age group time standard
Time standard for the next age group and the gap to reach it
Got the next age group’s time standard.

Short Course Distance

Event	Best Time	Sectionals	18U Spring Cup	Futures	Jrs - Winter	US Open	Summer Champ	SouthWestern Age Group Regional
Free 50 Y	31.74	24.89 (+6.85s \| 21.6%)	23.89 (+7.85s \| 24.7%)	23.89 (+7.85s \| 24.7%)	23.29 (+8.45s \| 26.6%)	22.59 (+9.15s \| 28.8%)	22.79 (+8.95s \| 28.2%)	30.89 (+0.85s \| 2.7%)
Free 100 Y	1:13.92	53.99 (+19.93s \| 27.0%)	51.89 (+22.03s \| 29.8%)	51.89 (+22.03s \| 29.8%)	50.39 (+23.53s \| 31.8%)	49.29 (+24.63s \| 33.3%)	49.69 (+24.23s \| 32.8%)	1:08.19 (+5.73s \| 7.8%)
Free 200 Y	2:51.64	1:56.29 (+55.35s \| 32.2%)	1:52.89 (+58.75s \| 34.2%)	1:52.29 (+59.35s \| 34.6%)	1:49.09 (+62.55s \| 36.4%)	1:46.69 (+64.95s \| 37.8%)	1:47.39 (+64.25s \| 37.4%)	2:29.09 (+22.55s \| 13.1%)
Back 50 Y	38.17	N/A	N/A	N/A	N/A	N/A	N/A	36.49 (+1.68s \| 4.4%)
Breast 50 Y	39.30	N/A	N/A	N/A	N/A	N/A	N/A	40.39 37.79 (+1.51s \| 3.8%)
Breast 100 Y	1:25.18	1:07.59 (+17.59s \| 20.7%)	1:05.49 (+19.69s \| 23.1%)	1:05.49 (+19.69s \| 23.1%)	1:03.09 (+22.09s \| 25.9%)	1:01.79 (+23.39s \| 27.5%)	1:02.79 (+22.39s \| 26.3%)	1:27.99 1:22.09 (+3.09s \| 3.6%)
Breast 200 Y	3:08.84	2:28.19 (+40.65s \| 21.5%)	2:22.69 (+46.15s \| 24.4%)	2:22.69 (+46.15s \| 24.4%)	2:17.19 (+51.65s \| 27.4%)	2:13.59 (+55.25s \| 29.3%)	2:15.49 (+53.35s \| 28.3%)	N/A
Fly 50 Y	37.51	N/A	N/A	N/A	N/A	N/A	N/A	35.09 (+2.42s \| 6.5%)
Fly 100 Y	1:34.74	59.19 (+35.55s \| 37.5%)	56.59 (+38.15s \| 40.3%)	56.59 (+38.15s \| 40.3%)	54.69 (+40.05s \| 42.3%)	53.49 (+41.25s \| 43.5%)	53.99 (+40.75s \| 43.0%)	1:20.19 (+14.55s \| 15.4%)
IM 100 Y	1:20.68	N/A	N/A	N/A	N/A	N/A	N/A	1:17.69 (+2.99s \| 3.7%)
IM 200 Y	3:02.16	2:10.49 (+51.67s \| 28.4%)	2:06.39 (+55.77s \| 30.6%)	2:06.39 (+55.77s \| 30.6%)	2:02.19 (+59.97s \| 32.9%)	1:59.49 (+62.67s \| 34.4%)	2:00.59 (+61.57s \| 33.8%)	2:46.49 (+15.67s \| 8.6%)

Long Course Distance

Event	Best Time	Sectionals	18U Spring Cup	Futures	Jrs - Winter	US Open	Summer Champ	SouthWestern Age Group Regional

Progression

See how Mackenzie O'Brien is improving gradually by choosing the distance and the stroke you are interested in. You can also compare the Mackenzie's time to another swimmer's and even view their profile for more information about them.

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Meets

See all the meets Mackenzie O'Brien has participated in and her achievement. The last event displayed is the most recent. For each event, you can find the Mackenzie's time, the progress against Mackenzie's best time, the corresponding time standard, as well as how much faster Mackenzie needs to be to reach the next level.

Event

Time

Progress

Standard

Next Standard

Age

Heat

Lane

Ranking

2026 Little Blue Penguin Pentathlon

02/01/2026

Laurel

50 Y Free

31.98

+0.24s

AA: 30.89 (+1.09s | 3.4%)

50 Y Back

39.51

+1.34s

A: 37.99 (+1.52s | 3.8%)

50 Y Breast

39.30

-0.03s (New PB)

AAA: 38.89 (+0.41s | 1.0%)

100 Y IM

1:22.70

+2.02s

A: 1:22.09 (+0.61s | 0.7%)

50 IM

38.79

100 IM

43.91

1:22.70

100 IM

1:22.70

50 Y Fly

38.50

+0.99s

A: 36.99 (+1.51s | 3.9%)

PVS January Open 2026 Fairland

01/17/2026

Laurel

100 Y IM

1:20.68

-1.27s (New PB)

AA: 1:18.39 (+2.29s | 2.8%)

50 IM

39.62

100 IM

41.06

1:20.68

100 IM

1:20.68

100 Y Fly

1:34.74

A: 1:26.09 (+8.65s | 9.1%)

50 Fly

43.66

100 Fly

51.08

1:34.74

100 Fly

1:34.74

50 Y Back

38.39

+0.22s

A: 37.99 (+0.40s | 1.0%)

50 Y Free

31.74

-0.73s (New PB)

AA: 30.89 (+0.85s | 2.7%)

50 Y Fly

37.51

-0.88s (New PB)

A: 36.99 (+0.52s | 1.4%)

200 Y IM

3:02.16

A: 2:55.49 (+6.67s | 3.7%)

50 Fly

41.36

100 Back

48.97

1:30.33

100 IM

1:30.33

150 Breast

49.21

2:19.54

200 Free

42.62

3:02.16

100 IM

1:31.83

100 Y Free

1:14.96

+1.04s

A: 1:11.49 (+3.47s | 4.6%)

50 Free

35.64

100 Free

39.32

1:14.96

100 Free

1:14.96

2025 Katie Ledecky Invitational

12/11/2025

College Park

100 Y Breast

1:28.97

+3.79s

AAA: 1:24.69 (+4.28s | 4.8%)

50 Breast

41.35

100 Breast

47.62

1:28.97

100 Breast

1:28.97

100 Y IM

1:21.95

AA: 1:18.39 (+3.56s | 4.3%)

50 IM

37.86

100 IM

44.09

1:21.95

100 IM

1:21.95

50 Y Free

32.47

-0.13s (New PB)

A: 32.09 (+0.38s | 1.2%)

50 Y Fly

38.39

-0.15s (New PB)

A: 36.99 (+1.40s | 3.6%)

50 Y Breast

39.33

-0.33s (New PB)

AAA: 38.89 (+0.44s | 1.1%)

100 Y Free

1:13.92

-1.11s (New PB)

A: 1:11.49 (+2.43s | 3.3%)

50 Free

34.27

100 Free

39.65

1:13.92

100 Free

1:13.92

50 Y Back

39.34

+1.17s

A: 37.99 (+1.35s | 3.4%)

2025 PV October Open Fairland

10/10/2025

Laurel

50 Y Free

32.60

-0.14s (New PB)

A: 32.09 (+0.51s | 1.6%)

100 Y Breast

1:25.18

AAA: 1:24.69 (+0.49s | 0.6%)

50 Breast

39.27

100 Breast

45.91

1:25.18

100 Breast

1:25.18

200 Y Breast

3:08.84

50 Breast

41.17

100 Breast

48.88

1:30.05

100 Breast

1:30.05

150 Breast

48.93

2:18.98

200 Breast

49.86

3:08.84

100 Breast

1:38.79

50 Y Breast

39.66

AAA: 38.89 (+0.77s | 1.9%)

50 Y Fly

38.54

A: 36.99 (+1.55s | 4.0%)

50 Y Back

38.17

A: 37.99 (+0.18s | 0.5%)

100 Y Free

1:15.03

-1.47s (New PB)

A: 1:11.49 (+3.54s | 4.7%)

50 Free

35.40

100 Free

39.63

1:15.03

100 Free

1:15.03

2025 PAC All Freestyle Meet

09/27/2025

Laurel

100 Y Free

1:16.50

A: 1:11.49 (+5.01s | 6.5%)

50 Free

35.63

100 Free

40.87

1:16.50

100 Free

1:16.50

50 Y Free

32.74

A: 32.09 (+0.65s | 2.0%)

200 Y Free

2:51.64

A: 2:38.39 (+13.25s | 7.7%)

50 Free

36.06

100 Free

43.02

1:19.08

100 Free

1:19.08

150 Free

47.42

2:06.50

200 Free

45.14

2:51.64

100 Free

1:32.56

Disclaimer: This Website is not affiliated with USA Swimming or any Local Swim Committee. The rankings and times displayed on this website are unofficial and should not be viewed as such. We update our information regularly, but we cannot guarantee that the data is accurate, timely, or complete. The only purpose of this website is entertainment. None of the information here should be used for university admission applications.