Open Graph Protocol Research

Why This Matters

The Open Graph Protocol (OGP) is arguably the most successful entity schema ever deployed. 69.8% of all websites use Open Graph (W3Techs, Jan 2026), making it the dominant structured data format on the web. Every og:type, og:title, og:image tag follows this spec. It defines how arbitrary web content becomes typed objects with properties and relationships.

Key insight: OGP solved the “how do you type everything on the web?” problem with radical simplicity. We can learn from their type hierarchy and design philosophy.

FINDINGS

History & Origins

April 21, 2010 — Mark Zuckerberg announced the Open Graph Protocol at Facebook’s F8 developer conference, calling it “the most transformative thing we’ve ever done for the Web.”

The initiative launched with three components:

Social Plugins (Like button) — Simple HTML embeds, one line of code
Open Graph Protocol — Metadata standard to turn web pages into graph objects
Graph API — New developer platform

Design Goal: Developer simplicity. The protocol was designed so publishers could “copy and paste” meta tags.

Within 7 days of launch: Hosting services, libraries, and a WordPress plugin had been created.

Influences

OGP was inspired by and builds on:

Dublin Core — Foundational web metadata vocabulary
RDFa — Embedding structured data in HTML (OGP is RDFa-based)
Microformats — Lightweight semantic markup
link-rel canonical — URL canonicalization

Evolution Timeline

Date	Event
April 2010	OGP announced at F8 with Like button
October 2009	Open Graph API concept first unveiled
January 2012	OGP 1.1 released, reduced types from 39 to 12
October 2012	Custom Open Graph actions deprecated (auto-posting)
May 2019	Open Graph Stories deprecated (render as plain links)
August 2018	`publish_actions` permission removed from Facebook Login

Notable: OGP 1.0 defined 39 object types. OGP 1.1 simplified to 12 global types. Types like “band” and “musician” were consolidated into “profile”.

KEY PEOPLE

Person	Role	Organization	Era
Mark Zuckerberg	Announced OGP at F8	Facebook	2010
Bret Taylor	Director of Platform Products, led Open Graph development	Facebook	2009-2013
David Recordon	Senior Open Programs Manager, presented OGP design decisions	Facebook	2009-2012
Mike Schroepfer	Head of Engineering	Facebook	2010
Chris Messina	Critic/analyst, inventor of hashtag	Independent	2010
Niall Kennedy	Created PHP validator, documented OGP 1.1	Independent	2011-2012

Bret Taylor was the key technical leader. He joined Facebook when they acquired FriendFeed in 2009, led the Platform team, demonstrated OGP at F8 2010, and was promoted to CTO in June 2010.

David Recordon presented “The Open Graph Protocol Design Decisions” at W3C’s Linked Data Camp at WWW 2010 (April 29, 2010). He defended OGP’s “openness” — it’s licensed under Open Web Foundation Agreement, increases semantic web data, and isn’t proprietary to Facebook.

COMPLETE TYPE HIERARCHY

Required Properties (All Types)

Property	Type	Description
`og:title`	string	Title as it should appear in the graph
`og:type`	string	Object type (see below)
`og:image`	url	Image URL representing the object
`og:url`	url	Canonical URL (permanent ID in the graph)

Optional Properties (All Types)

Property	Type	Description
`og:audio`	url	Audio file URL
`og:description`	string	1-2 sentence description
`og:determiner`	enum	Article before title: “a”, “an”, “the”, "", “auto”
`og:locale`	string	Locale in `language_TERRITORY` format (default: `en_US`)
`og:locale:alternate`	string[]	Array of alternate locales
`og:site_name`	string	Parent website name (e.g., “IMDb”)
`og:video`	url	Video file URL

Structured Media Properties

og:image sub-properties:

og:image:url — Same as og:image
og:image:secure_url — HTTPS version
og:image:type — MIME type
og:image:width — Pixel width
og:image:height — Pixel height
og:image:alt — Alt text description

og:video — Same sub-properties as og:image

og:audio — Has :url, :secure_url, :type (no dimensions)

OBJECT TYPES (og:type values)

No Vertical (Global Types)

`website`

Namespace: https://ogp.me/ns/website#
Properties: None beyond basic metadata
Note: Default type. Any non-marked up page is treated as website

`article`

Namespace: https://ogp.me/ns/article#
Properties:
- article:published_time (datetime) — First published
- article:modified_time (datetime) — Last changed
- article:expiration_time (datetime) — Expiry date
- article:author (profile[]) — Writers
- article:section (string) — High-level section (e.g., “Technology”)
- article:tag (string[]) — Tag words

`book`

Namespace: https://ogp.me/ns/book#
Properties:
- book:author (profile[]) — Authors
- book:isbn (string) — ISBN
- book:release_date (datetime) — Release date
- book:tag (string[]) — Tags

`profile`

Namespace: https://ogp.me/ns/profile#
Properties:
- profile:first_name (string)
- profile:last_name (string)
- profile:username (string)
- profile:gender (enum: male, female)

`payment.link` (Beta)

Namespace: https://ogp.me/ns/payment#
Properties:
- payment:description (string)
- payment:currency (string) — ISO 4217 code
- payment:amount (float)
- payment:expires_at (datetime)
- payment:status (enum: PENDING, PAID, FAILED, EXPIRED)
- payment:id (string)
- payment:success_url (url)

Music Vertical

Namespace: https://ogp.me/ns/music#

`music.song`

music:duration (integer ≥1) — Length in seconds
music:album (music.album[]) — Albums containing this song
music:album:disc (integer ≥1) — Disc number
music:album:track (integer ≥1) — Track number
music:musician (profile[]) — Artists

`music.album`

music:song (music.song) — Songs on album
music:song:disc (integer ≥1)
music:song:track (integer ≥1)
music:musician (profile) — Artist
music:release_date (datetime)

`music.playlist`

music:song — Same structure as album
music:song:disc
music:song:track
music:creator (profile) — Playlist creator

`music.radio_station`

music:creator (profile) — Station creator

Video Vertical

Namespace: https://ogp.me/ns/video#

`video.movie`

video:actor (profile[]) — Actors
video:actor:role (string) — Role played
video:director (profile[]) — Directors
video:writer (profile[]) — Writers
video:duration (integer ≥1) — Length in seconds
video:release_date (datetime)
video:tag (string[])

`video.episode`

All properties from video.movie, plus:
video:series (video.tv_show) — Parent series

`video.tv_show`

Same properties as video.movie

`video.other`

Same properties as video.movie
For videos not fitting other categories

Business Vertical (Added 2013)

Namespace: https://ogp.me/ns/business#

`business.business`

Required:

place:location:latitude
place:location:longitude
business:contact_data:street_address
business:contact_data:locality
business:contact_data:country
business:contact_data:postal_code

Optional:

business:contact_data:region
business:contact_data:email
business:contact_data:phone_number
business:contact_data:fax_number
business:contact_data:website
business:hours:day, business:hours:start, business:hours:end

Product Type (E-commerce)

`product`

og:price:amount — Price
og:price:currency — Currency code (USD, EUR, etc.)
product:availability — Stock status
product:condition — Item condition (new, used, etc.)
product:brand — Brand name
product:retailer_item_id — Product ID

DATA TYPES

Type	Description	Example Values
Boolean	true/false	`true`, `false`, `1`, `0`
DateTime	ISO 8601 date/time	`2024-01-15T10:30:00Z`
Enum	Bounded set of strings	`male`, `female`
Float	64-bit signed floating point	`1.234`, `-1.2e3`
Integer	32-bit signed integer	`1234`, `-123`
String	Unicode characters	Any text
URL	http/https URL	`https://example.com`

DEPRECATED PROPERTIES

From the RDF schema, these are explicitly deprecated:

og:audio:title, og:audio:artist, og:audio:album
og:latitude, og:longitude (use place:location instead)
og:street-address, og:locality, og:region, og:postal-code, og:country-name
og:email, og:phone_number, og:fax_number
og:isbn (use book:isbn)
og:upc

EXTENSION MECHANISM

Custom Namespaces

OGP allows custom types using CURIEs (Compact URIs):

<html prefix="my_namespace: https://example.com/ns#">
<head>
  <meta property="og:type" content="my_namespace:my_type" />
</head>

Key distinction:

Global types use dot notation: video.movie, music.song
Custom types use colon notation: my_namespace:my_type

Facebook-Specific Extensions

Developers could create custom actions scoped to their Facebook application, though this was largely deprecated in 2012. Approved core actions remaining:

Like (any object)
Follow (profile)
Listen (song)
Read (article)
Watch (video/movie/TV show)

RELATIONSHIP TO OTHER STANDARDS

vs Schema.org

Aspect	Open Graph	Schema.org
Purpose	Social media sharing	Search engine SEO
Created by	Facebook (2010)	Google, Microsoft, Yahoo, Yandex (2011)
Adoption	69.8% of web	52.6% (JSON-LD)
Complexity	Simple, ~12 types	Complex, 800+ types
Implementation	Meta tags in `<head>`	JSON-LD, microdata, RDFa
Relationship modeling	Minimal	Rich

Key insight: OGP optimizes for the “link preview” use case. Schema.org optimizes for the “understand everything about this page” use case. Use both.

vs Twitter Cards

Twitter Cards are based on Open Graph conventions. Twitter’s parser:

Checks for Twitter-specific tags (twitter:card, twitter:title, etc.)
Falls back to Open Graph tags if Twitter tags missing

Twitter Card Types:

summary — Default card with thumbnail
summary_large_image — Large image card
player — Video/audio player
app — App download card

Platform Support

Platform	OGP Support	Notes
Facebook	Full	Creator of OGP
LinkedIn	Full	Uses OGP for link previews
Twitter/X	Partial	Prefers Twitter Cards, OGP fallback
Pinterest	Partial	Prefers Schema.org for Rich Pins
Slack	Full	Uses OGP for “unfurling”
Discord	Full	Uses OGP for embeds
WhatsApp	Full	Uses OGP for link previews
iMessage	Full	Uses OGP for rich links

IMPLEMENTATION BEST PRACTICES

Required Tags

<html prefix="og: https://ogp.me/ns#">
<head>
  <meta property="og:title" content="Page Title" />
  <meta property="og:type" content="website" />
  <meta property="og:image" content="https://example.com/image.jpg" />
  <meta property="og:url" content="https://example.com/page" />
</head>

Image Requirements

Platform	Recommended Size	Min Size	Max File Size
Facebook	1200×630px	600×315px	8MB
LinkedIn	1200×627px	401px wide	5MB
Twitter	1200×628px	120×120px	5MB
General	1200×630px (1.91:1)	200×200px	5MB

Common Mistakes

Missing og:image — Results in no preview image
Relative URLs — Must use absolute URLs
Images too small — Won’t display or will show as tiny thumbnail
Description too long — Keep under 160 characters
Not pre-caching — First share may not show image

Validation Tools

Facebook Sharing Debugger: https://developers.facebook.com/tools/debug/
LinkedIn Post Inspector: https://www.linkedin.com/post-inspector/
Twitter Card Validator: https://cards-dev.twitter.com/validator
Open Graph Debugger: https://ogdebugger.com/

URLS

Official

https://ogp.me/ — Official specification
https://ogp.me/ns/ogp.me.ttl — RDF schema (Turtle format)
https://github.com/facebook/open-graph-protocol — GitHub repo
https://developers.facebook.com/docs/sharing/webmasters — Facebook implementation guide
https://developers.facebook.com/tools/debug/ — Sharing Debugger

Historical

https://www.scribd.com/doc/30715288/The-Open-Graph-Protocol-Design-Decisions — David Recordon’s WWW 2010 presentation
https://www.niallkennedy.com/blog/2012/01/open-graph-protocol.html — OGP 1.1 deep dive

News Coverage (F8 2010)

Comparisons

https://yext.com/blog/2017/07/schema-vs-open-graph — Schema.org vs OGP
https://w3techs.com/technologies/details/da-opengraph — Usage statistics

ENTITY TYPE OBSERVATIONS

What OGP Got Right

Radical simplicity — Only 4 required properties. Anyone can implement.
Pragmatic type system — 12 core types cover 90% of web content. Not trying to model everything.
Flat inheritance — Types don’t deeply inherit. video.movie isn’t a subtype of video that’s a subtype of media. Each type stands alone.
Verticals as namespaces — music.*, video.* group related types without inheritance complexity.
References over embeddings — article:author references a profile by URL, doesn’t embed the data. Follows graph principles.
Arrays for multiplicity — Multiple images, authors, tags handled by repeating the same property.
Structured properties — og:image has sub-properties like og:image:width. Clean way to add metadata without new top-level properties.

Type System Design Lessons

OGP Pattern	Our Application
4 required + many optional	Core entity properties: id, type, title, created
Vertical namespaces	Category-based type grouping
URL-based references	Entity relationships by ID
Structured sub-properties	Nested metadata
Enum constraints	Status fields, type restrictions
DateTime for temporality	created, modified, published

Types We Might Adopt

From OGP’s proven types:

article → Note, Document
book → Reference
profile → Person, Contact
video.movie, video.episode → Media items
music.song, music.album → Media with relationships
product → Item with price/availability
business.business → Place with contact info

Relationship Patterns

OGP models relationships through:

Type references — video:series points to a video.tv_show
Profile arrays — article:author is an array of profile references
Nested metadata — music:album:track gives position within container

This is reference-based, not join-table-based. The relationship lives on the referring object.

OGP 1.0 Complete Type List (39 Types)

Original types from May 2010 (via Wayback Machine):

Category	Types
Activities	`activity`, `sport`
Businesses	`bar`, `company`, `cafe`, `hotel`, `restaurant`
Groups	`cause`, `sports_league`, `sports_team`
Organizations	`band`, `government`, `non_profit`, `school`, `university`
People	`actor`, `athlete`, `author`, `director`, `musician`, `politician`, `public_figure`
Places	`city`, `country`, `landmark`, `state_province`
Products/Entertainment	`album`, `book`, `drink`, `food`, `game`, `product`, `song`, `movie`, `tv_show`
Websites	`blog`, `website`, `article`

Note: OGP 1.0 DID have organization types (band, company, government, non_profit, school, university) and place types (city, country, landmark). These were consolidated/deprecated in OGP 1.1 (2012).

Key Gaps Analysis

Type	OGP 1.0	OGP Current	Status
Event	❌ Never existed	❌ None	Facebook Events are Graph API objects, not OGP
Place	✅ city, country, landmark, state_province	❌ Deprecated	Properties deprecated in RDF schema
Organization	✅ band, government, non_profit, school, university, company	⚠️ Only `business.business`	Consolidated

Why no Event type? Facebook Events exist in the Graph API (proprietary), but external event websites just use og:type="website". The OGP philosophy is “link preview metadata” not “comprehensive entity typing.”

Session Log

2025-01-24: Initial setup

Created research doc
Outlined research tasks

2026-01-24: Phase 1 Web Research Complete

Fetched and documented full ogp.me specification
Retrieved RDF schema with all properties and deprecated items
Documented complete type hierarchy with all properties per type
Found key people: Bret Taylor, David Recordon, Mark Zuckerberg
Documented OGP history: April 21, 2010 F8 announcement
Tracked evolution: OGP 1.0 (39 types) → OGP 1.1 (12 types)
Compared to Schema.org, Twitter Cards
Found adoption statistics: 69.8% of web uses OGP
Documented extension mechanism (custom namespaces)
Listed all deprecated properties from RDF schema
Compiled implementation best practices
Identified lessons for entity type design

2026-01-24: Deep-dive on Event/Place/Organization

Confirmed: OGP NEVER had event type
Confirmed: OGP 1.0 HAD place types (city, country, landmark) — now deprecated
Confirmed: OGP 1.0 HAD organization types (band, company, government, etc.) — now consolidated into business.business
Decision: Use OGP as foundation, add event/place/organization ourselves