Most podcast directories — including Apple Podcasts, Spotify, Amazon Music, and others — expect your podcast to meet a similar baseline before they'll accept it. Meeting these requirements first will save you time when submitting to any individual platform.
Artwork
Your podcast artwork should be a square image, at least 1400 x 1400 pixels (and no larger than 3000 x 3000), in jpg or png format. If using png, make sure it's saved in RGB color space, not CMYK — directories will reject CMYK images. A 1400 x 1400 jpg is the recommended sweet spot for compatibility across platforms.
A unique podcast title
Your title should be distinct from other shows. Search for your intended title on Google and within podcast apps before finalizing it — exact matches are often rejected, and very similar titles may be flagged during review.
A description
Most directories require a short description of your show that helps listeners understand what it's about.
A valid email address
Directories use this to send notifications about your listing — new features, requirement changes, or issues with your feed. Use an address you check regularly, with good spam filtering.
At least one published episode
Your podcast needs at least one publicly accessible episode before most directories will accept it. The episode must be published, not saved as a draft.
Some directories have additional requirements beyond this baseline — check the specific submission article for the platform you're submitting to.