A 24-hour comic is a 24-page comic book written, drawn, and completed in 24 hours. Scott McCloud originally came up with the challenge for himself and Stephen R. Bissette as a creative exercise. McCloud drew the first 24-hour comic to prove it could be done on August 31, 1990, and Bissette did his on September 5.
Word of the challenge slowly spread, especially as Dave Sim published his own 24-hour comic, as well as those of McCloud, Bissette, and Neil Gaiman, in the back of his popular Cerebus the Aardvark. Eventually Scott McCloud had collected six 24-hour comics on his website from different, well-known comic-creators. Creators Erik Larsen and Chris Eliopoulos published their 24-hour stories together in the one-shot comic Image-Two-In-One featuring The Herculean and Duncan ("The Herculean" being Larsen's creation, and "Duncan" being Eliopoulos').
As originator of the challenge, Scott McCloud has established rules for a comic to qualify: It must be begun and completed within 24 consecutive hours. Only one person may be directly involved in its creation, and it must span 24 pages, or (if an infinite canvas format webcomic is being made) 100 panels.
The creator may gather research materials and drawing tools beforehand, but cannot plan the comic's plot ahead of time or put anything on paper (such as designs and character sketches) until he is ready for the 24 hours to begin. Any breaks (for food, sleep, or any other purpose) are counted as part of the 24 hours.
If the cartoonist fails to finish the comic in 24 hours, there are two courses of action suggested: Stop the comic at the 24-hour mark, or continue working until all 24 pages are done. The former is known as "the Gaiman variation" after Neil Gaiman's unsuccessful attempt, and the latter is called "the Eastman variation" after Kevin Eastman's unsuccessful attempt. Scott McCloud calls both of these "noble failures", which he will still list on his site as long as he believes that the creator intended to finish the project within the specified amount of time.
Nat Gertler organized 24 Hour Comics Day on April 24, 2004. On this day, comics creators around the world were invited to spend the day making a 24-hour comic. All participants were requested to send their completed comic to McCloud, who keeps an archive of all completed 24-hour comics on his webpage. Many comic book stores supported this event by setting up space for participating artists to work on their comic. It attracted many writers and artists, working both in print and web media.
|Year||Date||Number of participants|
|2005||April 23||Approximately 800|
|2006||October 7||Approximately 1200|
In 2005, the second annual 24 Hour Comics Day began on Saturday April 23, such that the 24 hours ended on the 24th, with over 800 cartoonists taking part at organized events with other folks taking the challenge at home. 2006's 24 Hour Comics Day fell on October 7 of that year, and had over 1200 participants at official event locations in 17 countries around the globe.
Leadership of 24 Hour Comics Day has been passed over to ComicsPRO, a U.S.-based comic book retailer organization. They held the 2008 event on October 18.
Lo Spazio Bianco organized 24 Hour Italy Comics Day, a similar event for creators in Italy, beginning on October 1, 2005, with authorization from McCloud and Gertler. Information can be found on the event's web site: 
The School of Visual Arts hosts a 24-hour Comic Day every year, but due to classes, the date isn't set.
Since 2006 Comicworld (www.comicworld.gr) is responsible for organizing the event in the Greek cities of Athens & Thessaloniki. In 2006 they gathered more than 50 participants in the same place. Every year they publish a graphic novel with the best three stories created in the event.
Similar challenges 
The 24-hour comics idea has inspired similar challenges in other art forms. There is also the 24 Hour Plays, in which a group of playwrights/actors script and perform a full play by the end of 24 hours. This, in turn, gave birth to the 48 Hour Film Project. The International 3-Day Novel Contest started in Vancouver in 1977 and now happens all over the world every Labour Day Weekend. The 24 Hour RPG project, started in 2003, asks designers to produce a playable tabletop role-playing game in 24 hours, and does frequent 'Grand Events' which assign a theme and a time window for designers to compete.
Five books of 24-hour comics have been published:
- 24 Hour Comics (ISBN 0-9716338-4-3) presents nine comics selected by Scott McCloud.
- 24 Hour Comics Day Highlights 2004 (ISBN 0-9753958-0-7) presents selections from the 2004 event, edited by Nat Gertler.
- 24 Hour Comics All-Stars (ISBN 0-9753958-4-X) presents comics by several professional cartoonists, edited by Nat Gertler.
- 24 Hour Comics Day Highlights 2005 (ISBN 0-9753958-6-6) presents selections from the 2005 event, edited by Nat Gertler.
- 24 Hour Comics Day Highlights 2006 (ISBN 0-9790750-0-9) presents selections from the 2006 event, edited by Nat Gertler.
- "ComicsPRO Opens Registration for 24 Hour Comics Day 2008". Comic Related. Retrieved September 27, 2009.
- The 24-hour Comics - Original homepage.
- 24-hour Comics Index - List of 24-hour comics. (incomplete and no longer updated)
- 24HourComicsDay.com - Information about the annual event.
- 24 hours Comic Vienna