What's the most standard comic books formats for e-book publishers and comics publishers?

Question

What's the most standard comic books formats for e-book publishers and comics publishers? I am thinking because there are a lot of mobile devices and printing machines, there must be some standards for jpg files when trying to publish a comics book. What are these format (size)?

Answer 1

6.625 x 10.25 inch (approximately 17 x 26 cm) seems to be the standard comic book size* (5.04" x 7.17" for manga).

If you draw the pages on paper, you want to do so at 150% of the final size†‡. If you want your art to cover the full page, you also need to take bleed into account: When they trim the book to size, the edges will be cut off. There should be art there, but not art that matters. The safe viewing area is ~ 6 x 9 inch (i.e. the area you can be sure won't be trimmed.)

If you create digital art, keep in mind the printing resolution. You'll want to use at least 300 dpi, possibly 600. Taking the first option, you'll want a canvas of around 2100 x 3150 pixels. Any size above that with approximately 2 x 3 aspect ratio is fine, since you can scale down. (If you use vector graphics, pixels don't matter, it scales to any size.)

You'll want to keep the original files (e.g. photoshop) for printing, but if you want to publish online, you can export to JPG or PNG. PNG is a lossless format, so it will be a bigger file size, but also won't have any compression artifacts. JPG will be a much smaller file size, but if you use a high compression the quality degrades. You can also reduce the resolution for putting it online, 75 or 100 dpi is common for images on the web, which means a reduction in pixel-size by a factor of 3 or 4 if you start with 300 dpi.

If you follow these guidelines, then I very much doubt that the format will be what's holding you back from getting published.

* https://support.comixology.com/hc/en-us/articles/360042720994-What-size-and-file-format-should-my-pages-be provides examples of standard sizes and canvas size at different DPI (without bleed)
† http://www.phillipginn.com/comic-book-page-sizing-guide has an example of the author's process of turning art to printed page
‡ https://mckelvie.tumblr.com/post/167235929653/comic-book-page-technical-specifications has a good illustrated guide of bleed, trim and viewing area.

You can find more information just searching: https://duckduckgo.com/?q=standard+comic+book+dimensions&t=h_&ia=web