The book

League records

Best-ever observed time per event across all loaded seasons. 56 events with at least one recorded swim.

How records work here

Each entry is the fastest legal time ever recorded for that event in the loaded data — across every ISL Championship PDF we've parsed. Records carrying multiple seasons of daylight get a Standing chip; records set this season get New. ISL is the ultimate authority on the official book — we display what the published results show.

Records in book

across all age groups

Oldest standing

18y

Ella Eastin, 2007

Age 5-6

Event	Holder	Time	Margin	Set
Girls 5-6 25 Backstroke	Linda Jiang NPF	19.35	+1.15s	2025New
Girls 5-6 25 Breaststroke	Linda Jiang NPF	22.00	+0.02s	2025New
Girls 5-6 25 Butterfly	Grace Wang PS	17.16	+0.80s	20214y
Girls 5-6 25 Freestyle	Emily Jiang NPF	16.35	+0.32s	2024New
Boys 5-6 25 Backstroke	Holden Levine TRS	18.53	+1.22s	201411y
Boys 5-6 25 Breaststroke	Sahiel Pai CSR	21.51	+0.27s	20196y
Boys 5-6 25 Butterfly	Holden Levine TRS	16.53	+1.86s	201411y
Boys 5-6 25 Freestyle	Holden Levine TRS	15.72	+1.24s	201411y

Age 7-8

Event	Holder	Time	Margin	Set
Girls 7-8 25 Backstroke	Tina Tang WBY	17.00	+0.41s	20223y
Girls 7-8 25 Breaststroke	Johanna Toney WP	19.15	+0.15s	20232y
Girls 7-8 25 Butterfly	Hope Heumann DF	15.58	+0.05s	20223y
Girls 7-8 25 Freestyle	Maya Nishizaka WB	14.74	+0.02s	20169y
Boys 7-8 25 Backstroke	Holden Levine TRS	15.96	+0.86s	20169y
Boys 7-8 25 Breaststroke	Taylor Thongintra CPS	18.46	+0.18s	20178y
Boys 7-8 25 Butterfly	Holden Levine TRS	14.67	+0.55s	20169y
Boys 7-8 25 Freestyle	Holden Levine TRS	13.34	+0.91s	20169y

Age 9-10

Event	Holder	Time	Margin	Set
Girls 9-10 100 IM	Ella Eastin NPR	1:05.02	+1.71s	200718y
Girls 9-10 50 Backstroke	Tina Tang WBY	31.42	+0.74s	2024New
Girls 9-10 50 Breaststroke	Hope Heumann DF	33.16	+0.93s	2024New
Girls 9-10 50 Butterfly	Ella Eastin NPR	28.63	+1.03s	200718y
Girls 9-10 50 Freestyle	Tina Tang WBY	27.01	+0.05s	2024New
Boys 9-10 100 IM	Nathan Wu SI	1:05.49	+0.57s	20178y
Boys 9-10 50 Backstroke	Derek Hitchens NPR	30.61	+0.98s	20178y
Boys 9-10 50 Breaststroke	Sahiel Pai NIK	33.25	+0.09s	20232y
Boys 9-10 50 Butterfly	Nicholas Chen WBY	28.72	+0.01s	20214y
Boys 9-10 50 Freestyle	Ian Sun PS	26.82	+0.01s	20187y

Age 11-12

Event	Holder	Time	Margin	Set
Girls 11-12 100 IM	Anna Heumann DF	1:00.08	+2.90s	2024New
Girls 11-12 50 Backstroke	Sydney Okubo WB	28.70	+0.16s	201213y
Girls 11-12 50 Breaststroke	Anna Heumann DF	31.00	+0.86s	2024New
Girls 11-12 50 Butterfly	Erin Li DF	26.45	+1.09s	2025New
Girls 11-12 50 Freestyle	Ariel Lin QH	25.08	+0.38s	20196y
Boys 11-12 100 IM	Sahiel Pai NIK	56.10	+1.20s	2025New
Boys 11-12 50 Backstroke	Nathan Wu SI	26.37	+0.87s	20196y
Boys 11-12 50 Breaststroke	Sahiel Pai NIK	27.44	+1.85s	2025New
Boys 11-12 50 Butterfly	Sahiel Pai NIK	25.20	+0.74s	2025New
Boys 11-12 50 Freestyle	Jacob Wang DF	23.32	+0.81s	20196y

Age 13-14

Event	Holder	Time	Margin	Set
Girls 13-14 100 IM	Anna Heumann DF	59.22	+0.43s	2025New
Girls 13-14 50 Backstroke	Ella Eastin NPR	27.30	+0.19s	201015y
Girls 13-14 50 Breaststroke	Anna Heumann DF	30.37	+0.86s	2025New
Girls 13-14 50 Butterfly	Zara Masud WP	25.80	—	20214y
Girls 13-14 50 Freestyle	Holly Fishburn WB	24.50	+0.02s	2024New
Boys 13-14 100 IM	Nathan Wu SI	52.70	+0.91s	20214y
Boys 13-14 50 Backstroke	Nathan Wu SI	24.51	+0.41s	20214y
Boys 13-14 50 Breaststroke	Nathan Wu SI	26.86	+0.69s	20214y
Boys 13-14 50 Butterfly	Chris Leung NPF	23.14	+0.47s	20196y
Boys 13-14 50 Freestyle	Jacob Wang DF	21.03	+0.93s	20214y

Age 15-18

Event	Holder	Time	Margin	Set
Women 15-18 100 IM	Zara Masud WP	58.44	+0.42s	2024New
Women 15-18 50 Backstroke	Malia Allen PS	26.84	+0.06s	20178y
Women 15-18 50 Breaststroke	Kate Lee CLR	30.06	+0.37s	20178y
Women 15-18 50 Butterfly	Zara Masud WP	25.07	+0.54s	2024New
Women 15-18 50 Freestyle	Ariel Lin QH	23.81	+0.13s	20223y
Men 15-18 100 IM	Chris Leung NPF	50.26	+0.17s	20223y
Men 15-18 50 Backstroke	Andrew Knoell SI	23.09	+0.66s	20178y
Men 15-18 50 Breaststroke	Taylor Thongintra CPS	25.52	+0.27s	2025New
Men 15-18 50 Butterfly	Jacob Wang DF	21.90	+0.11s	2025New
Men 15-18 50 Freestyle	Jacob Wang DF	20.25	+0.04s	2024New

20 records set or matched in the most recent season.