We’re often asked if a Flash site can be indexed by search engines. This is one of those seemingly simple questions with a fairly complicated answer. The fact of the matter is that yes, Flash content can be made available to search engines; however, to do it properly requires some extra work.

A Flash Player for Google

Last July, Adobe announced that they are working with search engines to make Flash content natively searchable. They have provided technology to allow search engines to read content within SWF files, understand how it is organized on the screen, and follow links to additional screens contained within the file. This player allows search engine companies to write software that can read and crawl through Flash content much like it can with HTML.

It will likely be a while before search engines are able to fully understand content within a complex Flash site and it may be that Flash content will never rank as highly as similar content presented in HTML format. Fortunately, there is another way to expose the content used in your Flash files to search engines.

Progressive Enhancement

Progressive enhancement is a long standing approach to web development in which basic information is provided and then enhanced within the capabilities of the browser. The use of Cascading Style Sheets (CSS) to provide layout for HTML pages is perhaps the most common example of progressive enhancement on the web.

When applying this concept to Flash content, the strategy is to provide HTML content as a base-line and use JavaScript to replace that content with a SWF movie capable of rendering it. Using this technique, you can provide all the content displayed by your Flash movie to search engines and other non-flash enabled browsers as standards-based, semantic HTML. Visitors with Flash enabled will not see this HTML content, instead they are shown the richer Flash version.

SWFObject greatly simplifies this process for developers. It will handle the Flash Player detection as well as overwriting a specific div within your page with the appropriate Flash embed tag.

Progressive enhancement is commonly used to improve the display of media content on an HTML page. An example of this is the map for the Museum of Science and Industry. The HTML on this page includes four images along with alternate text and titles which are indexed by search engines. Users with Flash see a single floor of the museum at a time with easy-to-use navigation and helpful overlays of additional information.

The MSI map. HTML only (left) and Flash enhanced (right)

This technique can also be used to provide an overview of a large, media rich flash site such as NVIDIA Speak Visual. Here, basic information about the site is provided within the HTML giving that information higher relevance within search engines than if it were only included as keywords and other meta-data.

NVIDIA Speak Visual Homepage. HTML only (left) and Flash enhanced (right)

Multiple Pages

This basic progressive enhancement implementation can be expanded to support more than one page of content. The main challenge in this case is to provide distinct HTML pages for each of the screens within the Flash application.

For any given view, the server will deliver the appropriate HTML which is enhanced to Flash using the basic technique above. Subsequent views are loaded into the Flash application via XML (or another data format) without refreshing the browser page. So that search engines can find this content, each of these subsequent views must be available as HTML via links included in the HTML of the original view.

The net result is a series of URLs that the search engine will index as it would for any site with multiple pages. When a link to the site is followed from a search engine, the Flash application must support linking directly to the specific view requested rather than loading the top level of the site. Using SWFAddress facilitates this by setting up a system of views identified by unique URLs that are passed into the Flash application by SWFObject.

Searchable Flash Today

Progressive enhancement is a standards compliant way to add richness and interactivity to your content and can also be used to make your Flash content searchable today. Since it works by providing HTML to the engines, your site will benefit from common SEO best practices like semantic markup, optimal keyword selection and inbound links.

For sites that require a rich experience that only Flash can deliver and full coverage within search engines, this technique will deliver excellent results. Nike Skateboarding, Disney.com and this Fiat Showroom are examples of Flash sites using variations on the basic techniques described here to provide content to search engines. All of them have been live for quite some time and continue rank highly within the engines.

If you know of other examples of Flash sites using progressive enhancement, let us know in the comments below.