SenSEO for Firefox

Created and maintained by Nico Steiner © 2012

SenSEO 2.0.0 is a bootstrap add-on - installing the add-on doesn't need a Firefox restart. It no longer integrates in Firebug but runs in it's own panel in the upper right corner of your browser. more details

General Information

SenSEO analyzes web pages and tells you how good they fulfill on-page Search Engine optimization criteria. It gives you:

In the current version SenSEO checks

New SenSEO 2.4.0 is on the road

SenSEO 2.4: Pages Crawler

SenSEO 2.4: Compare Inspect Results

Go to the Mozilla Addon-Site to download the current version of SenSEO.

SEO on-page criteria

First of all it is important to know how to deal with SEO. The SenSEO-rules try to follow the Google Webmaster Guidelines.

Google says:

Avoid tricks intended to improve search engine rankings. A good rule of thumb is whether you'd feel comfortable explaining what you've done to a website that competes with you. Another useful test is to ask, "Does this help my users? Would I do this if search engines didn't exist?"

So please keep this in mind whenever you try to push your site in SERPs (Search Engine Result Pages) and do SEO moderately.

Read more


For questions, ideas or problems go to SenSEO at Get Satisfaction.

SenSEO Twitter-Channel

I registered the account at Twitter. Follow the development of SenSEO and get links to interesting SEO ressources.

SEO's Toolbox Collection

I created the SEO's Toolbox Collection at Firefox Add-ons. This Collection bundels the best extensions for Search Engine Optimization.


I published a short german presentation of SenSEO at Slideshare.

Even more Optimization

There are some more useful Extensions increasing your on-page optimizations. Yahoo's YSlow Extension checks the performance of your site and helps you accelerate page load. Firefox Accessibility Extension helps you testing your web resources for functional accessibility features. Semantic Checker highlights semantic elements found in the page. Html Validator lets you validate your site. Try to keep the errors of your HTML pages to a minimum. The Web Developer Extension has some useful features like showing the document outline for checking correct headline hierarchy or disabling JavaScript for simulating this search engine restriction.

Aarron Walter published a very useful Findability Strategy Checklist and a Presentation at Slideshare explaining the facts mentioned in this Checklist.


I would like to say thank you to people helping SenSEO getting better by reporting issues, making suggestions for improvements or taking part in any other way.

Thanks to