OPML Viewer

How to use

1. 1Switch to Paste OPML and paste the markup of your file, or switch to Drop .opml file and drop the export directly onto the drop zone.
2. 2Read the document summary to confirm the OPML version, owner, outline count, feed count, category count, and nesting depth.
3. 3Review the validation errors and warnings panels. Each issue points at the exact outline node so you can find it in your source.
4. 4Expand and collapse the outline tree to inspect categories and feeds. Click any xmlUrl or htmlUrl to open the feed or site in a new tab.
5. 5Use the feeds table to copy or download a CSV of every RSS and Atom feed, or use the JSON tree, Markdown list, or reformatted OPML exports for migration and archiving.

About this tool

OPML Viewer opens any Outline Processor Markup Language file in your browser and turns it into something you can actually read, validate, and migrate. Paste OPML markup or drop an .opml file (read locally, never uploaded), and the tool parses it with the native DOMParser, walks the outline tree to any depth, and surfaces a document summary (OPML version, document title, owner, total outlines, RSS feed count, Atom feed count, category count, link count, and maximum nesting depth). A structural validator catches the issues real exports tend to ship with: missing version attribute on the root element, missing head or body, outline nodes missing the required text attribute (falling back to title with a warning when both are present), feed outlines that forget xmlUrl, link outlines that forget url, and include outlines that forget the included file URL. Every issue is reported with an XML path like opml > body > outline[2] > outline[5], so you can find the broken node in your source file in seconds. The interactive outline preview renders the whole tree as collapsible cards. Each card shows the resolved label, a type chip (RSS feed, Atom feed, Link, Include, or Category), and the xmlUrl and htmlUrl as clickable links that open in a new tab. The feeds table flattens every RSS and Atom outline into one row each with title, type, feed URL, site URL, and category trail, so you can copy or download a clean CSV ready for a spreadsheet or for bulk-importing into a different reader. Four export formats round out the tool: a full JSON tree with every attribute preserved, a feeds CSV, a Markdown nested list with feeds rendered as links, and a reformatted OPML file with canonical attribute order and two-space indentation. Useful for moving an RSS subscription list between Feedly, Inoreader, NetNewsWire, Reeder, The Old Reader, Feedbin, Miniflux, and FreshRSS; for migrating a podcast OPML between Pocket Casts, Overcast, AntennaPod, and Apple Podcasts; for inspecting an outline export from an outliner like OmniOutliner; and for sanity checking an OPML file you generated programmatically. Everything runs locally in your browser, so your subscription list never leaves your device.

Free to use. Works in your browser. No signup, no login.