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I'm not even sure if this would work as i'm not sure if we use the same template (HTML) for each of these 8 pages whether that would flag to Google that it is duplicate content ? In many regards there are entire sites which use the same template. The same header, footer, sidebar but the content itself is what's most important. As long as the content itself is unique, then it will be indexed if all other SEO factors are in place. Another thought we had around this was we could offer how to articles for each of the 850 different conversion types - this would be completely unique content and different for each conversion type. Well that can certainly work. It is very labor intensive. My main concern is you would be performing this work for search engines, not for the user experience, and as a result the best outcome would not be achieved. If you were to take this course, I would recommend to start with a few pages, ensure they rank well, then slowly expand the process. The challenge will be scalability. Once your first pages are complete it would become increasingly difficult (if not impossible) to continue to describe the process in a meaningful way which is unique. The #1 ranked site for the term offers a step-by-step guide and images: http://www.rersoft.com/aac-files/convert-aac-to-3g2-audio.html. Images connect very well with readers and offer you an opportunity to provide alt text which you can vary a bit. Before going down that path, what is the best course for users? It seems your home page is a fantastic tool which allows users to convert from any format, to any format. In many respects the entire /convert area of your site seems unnecessary. I get the impression it was created specifically for SEO purposes. My recommendation would be to adjust the main conversion types page a bit: http://www.zamzar.com/conversionTypes.php. Each extension would have it's own page on your site, but without a unique page covering every "from" and "to" possibility. The result of this approach would be a lot fewer pages, but each page would be more usable, more important and earn more links to them. Remember your pages can earn strong relevance with anchor text. A single page title "Converting 3G2 video files" with an anchor text link named "3G2 to AAC" can earn very strong relevance for the phrase even if that exact phrase does not appear on the page. I counted 16 different types of file types which a 3G2 format can be converted to on your site. What if those 16 pages were removed and 301'd to your main 3G2 page: http://www.zamzar.com/fileformats/3g2\. Next, make the 3G2 page a bit more readable and add a link to your converter (home page) at the top. My opinion is this latter approach would be a win for you and your visitors, which in turn can yield the best SEO benefits (i.e. ranking). If you still wish to try the other approach, there is no reason you can't do both. For the 3G2 extension, try one method. Then for the 3GP or another extension, try the other method. See which works best. Remember the method with consolidated category pages requires more link building efforts to be made. But, you save all the time writing those 16 different pages. If you have 2 employees working on this, track the amount of time spent writing and implementing those 16 pages, then spend an equal amount of time on quality link building efforts. Good luck.