Where Gretchen Walsh’s 54.33 Ranks Among the Greatest World Records in Swimming History

Gretchen Walsh’s 54.33 world record in the women’s 100 butterfly, set last Saturday at the Fort Lauderdale Open, was truly astonishing.

The level of dominance she has displayed in the event over the past few years has been remarkable. After all, she now owns the 13 fastest performances in history in the event — a distinction usually reserved for the greatest swimmers the sport has ever seen.

But beyond that, what may stand out even more is the gap she has created between herself and the rest of the field.

Sarah Sjostrom’s 55.48 world record, which stood from 2016 to 2024, now feels like a distant memory. So distant that Sjostrom — still the second-fastest performer in history with that swim — now sits 1.15 seconds behind Walsh’s world record. That is an enormous margin in a 100-meter race.

Walsh’s previous world record of 54.60 was already overwhelmingly dominant. In terms of the percentage gap to the second-fastest performer in history, it represented a 1.59% advantage — already the largest among all current world records. Now, that margin has grown to an incredible 2.07%.

That puts Walsh comfortably ahead of the second-largest gap among active world records in long course meters: Adam Peaty’s 56.88 in the men’s 100 breaststroke at 1.40%. On the women’s side, the closest comparison is Katie Ledecky in the women’s 1500 freestyle, where her record stands 1.21% ahead of the second-fastest performer ever.

 

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But what does that mean historically? Have there been other world records that were equally — or even more — dominant?

Being more than 2% faster than the second-fastest swimmer in history is an extraordinarily rare achievement. Very few swimmers have ever reached that level.

One of them is Peaty himself. When he set his still-standing 56.88 world record in the men’s 100 breaststroke at the 2019 World Aquatics Championships, the second-fastest performer in history had been 58.29. In other words, Peaty was an astonishing 2.42% faster.

Another example is Sjostrom. Her still-standing 24.43 world record in the women’s 50 butterfly, set in 2014, made her 2.55% faster than the previous record holder, fellow Swede Therese Alshammar.

To look for similarly dominant performances, my database research extended back to the late 1970s.

And since then, no world record in swimming has been more impressive than the legendary 2:05.96 that Mary T. Meagher posted in the women’s 200 butterfly at the historic 1981 U.S. National Championships.

Top LCM World Records Ranked by Percentage Gap to the 2nd-Fastest Performer (Since the Late 1970s) – One Entry per Swimmer per Event

Meagher had already been lowering the world record in the event since 1979, first with 2:07.01 and later with 2:06.37 — both more than 2% faster than the previous world record of 2:09.87 held by East German swimmer Andrea Pollack. By 1981, Pollack still ranked as the second-fastest performer ever, and Meagher’s 2:05.96 represented a staggering 3.01% advantage — something truly extraordinary. Not surprisingly, the performance was widely considered “Beamonesque” and the record lasted nearly 20 years.

Right behind Meagher’s 200 butterfly performance comes Meagher herself again, this time in the 100 butterfly. Her 57.93, also set at the 1981 U.S. Nationals, represented a 2.57% advantage over Pollack’s 59.46.

From the 2000s onward, the leaders in this category are Sjostrom in the 50 butterfly, followed by Inge de Bruijn — also in the 50 butterfly — and Peaty. Michael Phelps also appears on the list with his 1:52.09 world record in the 200 butterfly at the 2007 World Aquatics Championships. And then comes Gretchen Walsh’s 54.33.

All of this reinforces the magnitude of Walsh’s world record — a performance that, statistically speaking, belongs among the most impressive in the history of swimming.

Curiously, none of the records with gaps above 2% come from the 1990s. Truly extreme world records became more frequent in the 21st century. And interestingly, none were set during the supersuit era of 2008 and 2009.