How do you create a custom multireddit or custom feed?

Custom feeds — previously called multireddits — allow you to aggregate content from multiple communities into a single, unified feed that you can name, organize, and optionally share publicly. They are one of the most powerful organizational tools Reddit offers, particularly for users who have distinct interests they want to keep separate rather than mixing together in a single Home feed. According to detailed instructions in r/NewToReddit, creating a custom feed on desktop involves scrolling the left sidebar until you reach the Custom Feeds section and clicking "+ Create a custom feed." A dialog appears where you name the feed, add an optional description, and choose between making it private (only visible to you) or public (shareable with other users). After creating the feed shell, you add communities to it by visiting each subreddit, clicking the three-dot overflow menu in the upper right corner of the community page, and selecting "Add to custom feed." On the mobile app, the process is slightly different: tap the three horizontal bars in the upper left to open the sidebar, scroll to the bottom of your joined communities list to find "custom feeds," tap it, then tap "Add new custom feed" and give it a name. Once created, the feed appears in your sidebar and app menu as a permanent navigation shortcut. Adding communities on mobile involves going to the subreddit, tapping the overflow button, and selecting "Add to Custom Feed." Custom feeds hold up to 100 communities and function exactly like a subreddit feed in terms of sorting: you can sort by Hot, New, Top, or Rising. Importantly, you do not need to join a community to add it to a custom feed — you can aggregate posts from communities you follow quietly without adding them to your main feed or publicly visible subscription list. This makes custom feeds ideal for topic research, tracking competitor communities, or building thematic reading collections.