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GoodRelations in Google Rich Snippets

Breaking news: It seems that Google has started to extract and display price details from e-commerce sites if they are expressed using the GoodRelations vocabulary for rich-meta data in RDFa.

If you want to use that for your Web site, see the step-by-step instructions or pick a proper recipe for a particular industry from the GoodRelations cookbook.


  1. Go to and make sure you are on the US American page (click on " in English" if you are on the localized variant of Google for your country.)
  2. Enter the query hepp scsi product. (Direct Link)
  3. On the top of the search results page, click on "+ Show options...".
  4. A new column of options appears. Click on "More shopping sites" (towards the end of the menu).
  5. You will see that the snippet for the page will show the product price prominently displayed on the right, in bold, and with a dollar sign ($):


Does that matter for my site?

Yes, because Yahoo has recently published an analysis that shows how augmented search results, e.g. such showing price info, reviews, etc., achieve at 15 % higher click-through rate.

That means an increase of potential buyers on your page by 15%.

What is GoodRelations and RDFa?

GoodRelations is a standardized vocabulary for product, price, and company data that can (1) be embedded into existing static and dynamic Web pages and that (2) can be processed by other computers. This increases the visibility of your products and services in the latest generation of search engines, recommender systems, and other novel applications.

RDFa is a syntax for packing rich meta-data into existing Web page content in XHTML or HTML, standardized by the W3C, the organization that coordinates the World Wide Web technology stack.

How is the effect related to GoodRelations?

While there is no official announcement yet that Google is actually using GoodRelations price data for the improved snippets, we have collected quite some evidence that it is actually the GoodRelations rich mark-up in the page that causes the augmented display.

First, it seems that Google is using multiple techniques in parallel for identifying and extracting price information from pages:

  1. Mark-up using microformats supported by Google.
  2. Text-based heuristics from HTML 4.01 documents (we found some pages that don't seem to have neither microformats nor RDFa markup.)
  3. CSS / shop template-based heuristics
  4. GoodRelations rich meta-data in RDFa.

For example, in the case of the second result found via the query la mousson levante,, the improved snippet could have been based either on this part of the mark-up

<xml> ...

8,99 €

... </xml>

or on the GoodRelations mark-up in RDFa:

<xml> ...

... </xml>

But we have a lot of reason to assume that it's actually GoodRelations mark-up that is considered as part of the Google heuristics:

First, the page does not contain the price of $ 34.99 in the exact format used by Google in the snippet. The page contains "34.99 USD" instead.


Price: 34.99 USD


So it is clear that Google identifies this properly as a price and extracts the value and currency correctly.

But it could still be just a text-based heuristic.

Evidence for impact of GoodRelations + RDFa on Google Snippets from two Joomla Shops

However, we were able to find two Joomla/Virtuemart-based shops that differ just by their usage of GoodRelations. The one with GoodRelations mark-up produces a rich snippet with price information in Google, the standard one without does not.

Here is the evidence:

On with the option "show more shopping sites" enabled, compare the two queries

  1. Query A: silver and deming drill
  2. Query B: joomla ontology management

Appearance of a standard shop (no GoodRelations + RDFa)

The result page to query a) looks as follows:


If we look into the source code of the page,

we find the following markup (unedited - all whitespace as returned by the server):


     <td width="33%" valign="top" align="left">
     	Price per Unit (piece):      	




Appearance of an improved shop  (with GoodRelations + RDFa)

The result page to result page to query b) looks as follows:


If we look into the source code of the page

we find the following markup (unedited - all whitespace as returned by the server):


     <td width="33%" valign="top" align="left">
     	Price per Unit (piece):		


€81.23 (including 8.25 % tax)

You Save: 5.00%


Bottomline: The GoodRelations-augmented Joomla/Virtuemart shop operated by Alex Stolz, a staff member of my group, is shown with price information in Google, the standard one is not.

This is pretty strong evidence that it is actually the GoodRelations rich meta-data in RDFa that makes the difference.

How can I use GoodRelations for my page?


One could argue that since Google uses multiple techniques to identify and extract price information, it would not matter whether you use GoodRelations or any of the other techniques. However, there are three major advantages of using GoodRelations and RDFa:

  1. With GoodRelations, you can control what you send to Google and are not subject to errors in the other heuristics.
  2. If you use GoodRelations, you do not only feed Google's rich snippet technology, but also Yahoo SearchMonkey and any other of multiple upcoming applications that understand RDFa rich meta-data. Other approaches are limited to Google.
  3. Jay Myers from BestBuy has reported a very positive effect of GoodRelations + RDFa mark-up on the ranking in Google. While this cannot be proven in a controlled experiment, it is another potential benefit.