Theme Test Drive WordPress plugin allows you to safely test drive any theme on your blog as administrator, while visitors still use the default one. It happens completely transparently and they will not even notice you run a different theme for yourself. Best part is you can even set the testing theme options (if it has them) in the Admin panel while you are testing the theme.
Since version 2.0 Theme Test Drive features instant theme preview using a website thumbnail service.
You can also preview any theme by adding "?theme=xxx" to your blog URL. For example http://www.myblog.com/?theme=Default (theme name is case-sensitive!)
For all questions about the plugin please visit my WordPress forums.

Download
Installation & Usage
- Upload the plugin folder to your /wp-content/plugins/ folder.
- Go to the Plugins page and activate the plugin.
- Use the Options page to set the theme you want to test drive.
The selected theme will be visible only to blog administrator. Other visitors of the site will always see the default theme.
Note: if you use WP-Cache plugin, you might need to disable it (or setup to exclude pages)
Changelog
v2.6: Added user access level
v2.0:
- Instant theme preview using a live thumbnail preview
- Added "?theme=xxx" to your URL's to preview the desired theme. Example http://www.myblog.com/?theme=Default
Nov 29th, 2007 v1.0
* Initial release
Visit my other interesting WordPress Plugins or my WordPress theme Amazing Grace.
If you are looking forĀ WordPress consulting services feel free to contact me

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241 Comments
Awesome plug-in idea, but it looks like it no longer works with the latest version of WordPress, v3.0.1?
Please let the world know if it's updated.
Thanks,
Ansel
Awesome plugin, really easy to use and works kinda like Magic! Well done Vladimir ;)
Fantastic plugin. I am beside myself with gratitude! Thank you so much for sharing your expertise :)
Amazing... it works. Thanks form creating nice and useful plugin.
This plugin is amazing, and it WORKS with WP 3.01. I've been looking for something like this forever. Why isn't something like this bundled with WP?????
This is awesome.
Other theme switchers broke widget settings from theme to theme.
The ability to add an argument for a theme at the end of the URL (?theme=xxx) is the best part and spared me putting the theme switcher into the design.
Thanks!
Really nice job done there.
Works perfectly fine with wordpress 3.0.1 on my site
I've just have to force reaload and voila !!
I would like to use the Theme Test Drive plug-in. However, I see that VoiD says that this plug-in does not work with Word-Press 3.0 (post on June 18th). I have Word-Press 3.0. Has this plug-in been modified yet to work with Word-Press 3.0? If your answer is "no" or "not yet", this is ok-- I just need to know before I proceed with my website development. Thank you for your time.
It works normally with 3.0, WP is not always right
Hi! When i came to wordpress 3.0, theme test drive stop working. i very need it. help, plz.
I want to find a plugin which is related to theme managment ! Because I am going to build-up a themes sharing website which is similar to http://webcache.googleusercontent.com/search?q=cache:http://www.wordpressthemesbase.com/ Can anyone help me to find out that plugin use to manage themes download?
Thank you !