Atom Syndication Format Specification
Reference for Atom 1.0 (RFC 4287) feed and entry format for web content syndication.
Feed and Entry Structure
Atom feeds are XML documents with a feed element containing metadata and entry elements. Required feed elements: id, title, updated. Entries require id, title, updated, and recommend link and summary or content. Atom uses IRI (internationalized URIs) and supports multiple link types with rel attributes. The format is more rigorous and extensible than RSS. Content can be text, HTML, or XHTML.
- feed
- Container element
- entry
- Content item
- content
- text/html/xhtml
id, title, updatedid, title, updatedtype attributeExtensions and Comparison
Atom Publishing Protocol (AtomPub, RFC 5023) uses Atom for CRUD operations on web resources. Atom supports extensions via XML namespaces. Compared to RSS, Atom has stricter requirements, better date handling (RFC 3339), and cleaner extensibility. The format is used by many APIs and feed readers. Atom threads extension supports comment threading. The id must be a valid IRI and globally unique.
- AtomPub
- Publishing protocol
- dates
- RFC 3339 format
- vs RSS
- Stricter, more extensible
RFC 50232003-12-13T18:30:02ZIETF standard