Google Search
Google is one of several search-engines that index and support microformats.
main search
Google.com supports rel-nofollow, hCard, hReview, hReview aggregate, hProduct (since 2009-05-12 for rich snippets), hCalendar (since 2010-01-22), and hRecipe (since 2010-04-13) - in main search. See also related blog post on hCalendar hRecipe support.
rich snippets
Rich Snippets is Google's term for the enhancement of search results ("snippets") with information from microformats from pages.
- See google-rich-snippets-examples for documentation of Google's microformats examples.
- See google-rich-snippets-issues for issues with Google's Rich Snippets Testing tool.
people
Google's documentation on Rich snippets - People support
Details:
- at least two of the following must be present:
- title or role
- org
- adr
hCard properties supported (bold = required)
- fn
- nickname
- photo
- title
- role
- url
- org - "If fn and org have the exact same value, Google will interpret the information as referring to a business or organization"
- adr
- street-address
- locality
- region
- postal-code
- country-name
- friend (presumably from xfn)
- contact (presumably from xfn)
- acquaintance (presumably from xfn)
rel-me support:
organizations
Google's documentation on Rich snippets - Organizations support
Details:
- "Organization information (for example, details about a business such as a restaurant or attraction) that is marked up in the body of a web page can help Google understand location information in reviews or events."
- "It can also be displayed on a Place Page—a web page that organizes all relevant information about a place. more about rich snippets for local search
hCard properties supported (bold = required)
- fn/org - "use both fn and org, and ensure that these have the same value."
- url
- adr
- street-address
- locality
- region
- postal-code
- country-name
- tel
- geo
- latitude
- longitude
events
Google's documentation on Rich snippets - Reviews support
Multiple events:
Or a single event:
Details:
- "Event markup can be used to mark up events that occur on specific future dates, such as a musical concert or an art festival."
- "the name and location of the event, also needs to be clearly defined. Since this feature isn’t meant for advertising purposes, your event name should not contain any promotional elements such as the price of the event, a call to purchase, or an indication of a sale or temporary discount ."
hCalendar properties supported (bold = required)
- summary
- url - "Required for pages listing multiple events"
- location - "Required for single event. ... we recommend that you represent the location by using a nested Organization to specify a venue name and address." - hCard
- description
- dtstart
- dtend
- duration
- category
- geo
- latitude
- longitude
- photo
- tickets - "offer to buy tickets for the event. Can be a URL to a page where tickets can be purchased, or can include specific Offer properties, such as"
- price
- quantity
- priceValidUntil
- currency
reviews
Google's documentation on Rich snippets - Reviews support
Details:
- the main topic of the page needs to be about a specific product or service. For example, using review markup on a page containing multiple products is not supported.
- If the markup contains a single review, the reviewer’s name needs to be a valid name (Person or Organization)
- presumably an hCard
hReview properties supported (bold = required)
- item
- fn
- rating
- value
- best
- value-title support:
<span class="best"><span class="value-title" title="10"/></span>
- value-title support:
- worst
- "Tip: Don't add a separate hidden text block to specify the rating. Hidden content will not be displayed."[1]
- img alt number parsing:
<img class="rating" src="four_star_rating.gif" alt="4 Star Rating: Recommended" />
- value-title support:
<span class="rating"><span class="value-title" title="4.5" /></span>
- reviewer
- dtreviewed
- description
- summary
hReview-aggregate additional properties supported in addition to the above (or additional requirements / subproperties)
- count - "The total number of reviews for the item on your site. Note: Whenever you include count, the page must also contain review markup for each reviewed item. count should only include reviews on your own site."
- votes - "contributes toward the average rating but not towards the number of reviews available" - essentially, a "number of ratings" property.
- rating - required in their hReview-aggregate support
- rating
- average (additional subproperty)
- photo - though presumably this works in hReviews as well
recipes
Google's documentation on Rich snippets - Recipes support
Details:
- "When using recipe markup, the main topic of the page needs to be about a specific recipe. Using recipe markup on a page containing multiple recipes is not supported."
- "f the recipe markup contains a single review, the reviewer’s name needs to be a valid name (Person or Organization)." [[[hCard]]]
hRecipe properties supported (bold = required)
- fn
- tag
- photo
- published
- summary
- review - nested hReview
- prepTime - "length of time it takes to prepare the recipe for dish, in ISO 8601 duration format."
- min
- max
- cookTime - "time it takes to actually cook the dish, in ISO 8601 duration format."
- min
- max
- duration - "total time it takes to prepare the[sic] cook the dish, in ISO 8601 duration format."
- min
- max
- nutrition - "These elements are not explicitly part of the hRecipe microformat, but Google will recognize them."
- servingSize
- calories
- fat
- saturatedFat
- unsaturatedFat
- carbohydrates
- sugar
- fiber
- protein
- cholesterol
- instructions
- instruction
- yield
- ingredient
- name (not fn?)
- amount
- author - Can include nested Person information - hCard
products and listings
Google's documentation on Rich snippets - Products support and Product properties: hProduct in particular.
Details:
- "mark up your product information on a product page (a page that contains only a single product) or an aggregated offer page (a page that lists a single product, along with information about different sellers offering that product).
- "Because you cannot use microformats to indicate condition or availability (for example, "used" or "out-of-stock"), we recommend using hProduct only for new, in-stock products only."
hProduct properties supported (bold = required)
- fn ("name" in other vocabs)
- photo ("image" in other vocabs)
- brand
- description
- category
- review - a nested hReview aggregate
- (identifier - mentioned in other vocabs only)
- types: asin, isbn, mpn, sku, upc
- offerDetails - hListing - "An offer to sell the product. Includes a nested Offer or Offer-aggregate."
hListing (offers) properties supported (bold = required)
- fn (as part of item)
- price - "A floating point number. You may use either a decimal point ('.') or a comma (',') as a separator."
- currency - "currency used to describe the product price, in three-letter ISO format" (documented as "required", but testing tool doesn't report any error for omitting)
- url (for offers, offer-aggregates in particular)
- priceValidUntil - "date (in ISO date format) after which the price will no longer be available. (Your product snippet may not display if the priceValidUntil property indicates a past date.)"
- seller - hCard (Person or Organization)
- condition - "content" attribute must be one of: "new, used, refurbished"
- availability - "content" attribute must be one of: "out_of_stock, in_stock, instore_only, preorder"
- quantity
- identifier
- types: asin, isbn, mpn, sku, upc
- itemOffered - hProduct - "The item being sold. Typically, this includes a nested Product, but it can also contain other item types or free text."
Related: Offer-aggregate properties supported (bold = required)
- lowPrice - Floating point number
- highPrice - Floating point number
- currency - three-letter ISO format.
- offerCount
- condition - "content" attribute must be one of: "new, used, refurbished"
- offerURL
- identifier
- types: asin, isbn, mpn, sku, upc
- itemOffered - hProduct - "The item being sold. Typically, this includes a nested Product, but it can also contain other item types or free text."
There is an obsolete claim of non-support:
"We do not currently support the hListing format for product rich snippets."
Real world examples have disproven this, e.g.:
- http://www.smartmaster.co.il/Default.asp?sType=0&PageId=77222
- has several hListings with
class=hlisting - Google Structured Data Testing Tool shows extracted structured data
- 10 hListings, with
item/fn, andprice- all as marked up on the page.
- 10 hListings, with
- has several hListings with
advanced search
Through additional user interfaces:
- Google Advanced Search - Usage rights supports rel-license (since 2005(?) citation needed)
search APIs
- ...
previous support
Google often shuts down sites or services, and some of those were implementations.
Social Graph API
Google Social Graph API supported XFN (launched 2008 February). See "Google Social Graph API How are your sites connected?".