Microformats2

Microformats2 is a specification for embedding structured data in HTML by using simple, human-readable class names. It represents an evolution of the original microformats idea, aiming to make web content more easily machine-readable without requiring new scripting or complex data formats. The approach emphasizes lightweight, low-barrier annotation of common information directly in HTML pages.

The core mechanism of Microformats2 relies on class attributes to mark data types and properties. Top-level types use h- classes, such as h-card for contact information, h-event for calendar events, and h-entry for individual posts or articles. Within these containers, properties are indicated by prefixes: p- for plain text (for example, p-name), u- for URLs (u-url), and dt- for date and time (dt-published). This class-based system is designed to remain valid HTML and to be easily parsed by lightweight extractors.

In addition to class-based semantics, Microformats2 supports linking relationships through rel and rev attributes, which can convey associations between pages, authors, or sources. The format emphasizes coexistence with traditional HTML and simple extraction by clients, search engines, and bookmarking tools, rather than serving as a standalone data exchange format like JSON-LD or RDF.

Commonly used types include h-card for people or organizations, h-event for events, and h-entry for blog posts or articles. Microformats2 is maintained by the community via microformats.org and related documentation, reflecting a pragmatic approach to exposing structured data within ordinary web pages.

Status and reception: Microformats2 has found adoption in specific communities and tooling that favor minimalism and backward compatibility. It competes with broader formats such as schema.org and JSON-LD, but its lightweight, HTML-centric model continues to be valued for easy integration into existing pages.