PHOTO: IMAX/Marvel Studios
Now playing
01:27
How 'Avengers: Endgame' shattered records in 2019
PHOTO: Samantha Hartsoe
Now playing
02:24
Woman's bathroom mirror discovery goes viral
PHOTO: @neiltyson
Now playing
02:15
Colbert pokes fun at Neil Degrasse Tyson for vaccination photo
PHOTO: Stuart Weitzman
Now playing
00:39
Serena Williams and her daughter twin in new fashion ad
snl.fauci.vaccine.orig_00005420.png
snl.fauci.vaccine.orig_00005420.png
Now playing
01:24
'SNL' has 'Dr. Fauci' helping people get vaccinated
PHOTO: Instagram Lady Gaga
Now playing
00:56
Lady Gaga's 2 dogs returned home safely, LAPD says
PHOTO: Lewis Speaks
Now playing
01:13
Principal helps student with haircut issue
The Pokémon Company announced new games during its 25th Anniversary Celebration
PHOTO: The Pokémon Company
The Pokémon Company announced new games during its 25th Anniversary Celebration
Now playing
01:01
See the new Pokémon games coming soon
PHOTO: Maui63
Now playing
01:35
World's rarest marine dolphin finds protection in this flying friend
PHOTO: ABC's "Jimmy Kimmel Live!"
Now playing
01:46
Watch people struggle to identify second gentleman Doug Emhoff
PHOTO: nickelodeon/from youtube
Now playing
01:33
'Real World,' 'Frasier,' 'Spongebob:' See the reboots coming to this new streaming service
PHOTO: "The Late Late Show with James Corden" / Youtube
Now playing
01:37
See Prince Harry and James Corden tour LA on open-air bus
PHOTO: Harry Langdon/Archive Photos/Getty Images
Now playing
02:24
How Jane Fonda sparked a fitness revolution
jill biden kelly clarkson divorce advice orig mg_00001210.png
PHOTO: NBC / The Kelly Clarkson Show
jill biden kelly clarkson divorce advice orig mg_00001210.png
Now playing
01:12
Jill Biden opens up about divorce on Kelly Clarkson show
Fans Celebrate In Los Angeles After Lakers Win NBA Finals
PHOTO: (Photo by Brandon Bell/Getty Images)
Fans Celebrate In Los Angeles After Lakers Win NBA Finals
Now playing
01:14
Kyrie Irving says Kobe Bryant should be the NBA logo
PHOTO: 'GMA' / ABC
Now playing
01:56
Britney Spears' dad Jamie speaks out about conservatorship via lawyer on 'GMA'
(CNN) —  

The website Runpee.com has been around for more than a decade, advising movie-goers about the best time – should nature call – to run out for a bathroom break. Still, with this weekend’s release of the three-hour-plus “Avengers: Endgame,” the site/app might be ready for its closeup.

“This is as big a movie as we’ve ever done for Runpee,” Dan Gardner, the app’s founder, told CNN, adding that the app has just over 100,000 registered users.

Notably, it was another three-hour movie, Peter Jackson’s 2005 remake of “King Kong,” which gave Gardner the idea for the site. As he tells it, he needed to go but didn’t want to exit the theater, lest he miss a key scene.

Within a few years, that seed blossomed into an actual website/app, one that provides cues regarding when to leave without missing anything that’s fundamental to the plot or story. It is, of course, a somewhat subjective measure, which explains why the site also solicits feedback from film patrons.

If that sounds simple enough, it’s actually a bit more complicated, since Runpee usually offers more than one cue for each movie, and endeavors to word them so that they don’t contain spoilers. The app also provides information, should someone step out, about what they missed, approximating the role that a friend (who has the bad habit of talking during movies) would play.

On average, pee times usually look for a window of 3-4 minutes. Gardner cited “Captain America: The Winter Soldier” as an example of a movie with an excellent scene for taking a break, noting that good movies often have “really good pee times,” while bad ones frequently don’t.

“In most action movies, there’s the suiting up scene,” Gardner said. “That’s usually like the last pee time in the movie.”

The site has taken issue with Marvel Studios president Kevin Feige, who, in defending “Endgame’s” length, has stated that there won’t be time to pee during the movie.

“There is always time to pee,” Runpee countered in an open letter to Feige. “We offered Peetimes for roughly 169 movies last year alone, including three Peetimes for ‘Avengers: Infinity War.’ No offense.”

“Infinity War” ran about 2 ½ hours. With a 181-minute blockbuster that’s expected to break box-office records, in Runpee terms, “Endgame” could just be the perfect storm.