The Apple Podcast charts are designed for discovery

The exact algorithm is secret, but the charts’ purpose is to help listeners find new shows to listen to. To that end, Apple’s algorithm values recency and “hotness.”

Apple updates the charts frequently

Roughly once an hour, give or take. Websites like iTunesCharts.net can help you see historical chart data, but many of these sites take a daily snapshot, and don’t reflect the reality of hour-to-hour changes.

Each territory has it own set of charts

The US charts are different from the Canadian charts, which are different from the Brazilian charts. Apple publishes a list of territories on its website, and you can easily switch between territories in iTunes by clicking the circular flag in the bottom right corner:

A single show can appear on multiple charts simultaneously

But only if those charts belong to nested subcategories. For instance, Hackable? is listed in Tech News, which is a subcategory of Technology, which is a category under All Podcasts. This makes Hackable? eligible to chart in three categories at once:

All Podcasts

Technology

Tech News

Apple lists supported categories on their website. To increase your chances of charting, choose a subcategory (rather than a top-level category) as your primary <itunes:category> .

Apple’s charts only reflect activity within Apple’s ecosystem

Apple can only reliably track what happens on its own apps (iOS Podcasts and iTunes). Your show might get a lot of listener activity on other platforms (Pocket Casts, Overcast, CastBox, Spotify, your website, etc.) but that activity will not impact the Apple Podcast charts.

The Apple Podcast charts are available programmatically

To access a JSON or XML feed of top podcasts, use Apple’s RSS Generator tool.

Appearing on the Apple Podcast charts can kick off a virtuous cycle

The top charts are prominently displayed in Apple’s apps. Shows that make it to the Top 10 of a category often stay there, thanks to a positive feedback loop.

For example, take Hackable?, which quickly entered the Technology Top 10 at launch, and remained there for most of August and September 2017: