Content Files: Formats, Troubleshooting, Optimization ← Knowledge Base Can you provide some File Optimization Suggestions? Which is better, PDF or ePub? What if I don't have an ePub file? Are there any file size limitations or other restrictions on files uploaded into NetGalley? My file is too large for Kindle. What can I do? Where can I get more information about eBook files? Do you accept ePub 3 files? Can I create an InDesign preset to easily generate a PDF for NetGalley? Can I still use a PDF for the Kindle option if I don't have an epub available? Does NetGalley support .mobi files for Kindle? How can I optimize my ePub file? How can I reduce the size of my PDF? If I upload an epub file, how quickly will the mobi conversion happen? My file is taking a very long time to upload into the _INBOX. Will it take a long time for readers to open the file as well? What if I previously had Kindle disabled, but now wish to use the mobi conversion tool? Will NetGalley help me optimize my file? Do you use KindleGen for conversion of epub to .mobi?