I recently had to wipe a computer and get it up from scratch. In the process I realized that there are a series of tools I can not live without. This process also helped me realize how many tools I rely on and make a web developer’s life so much easier. Here is the run down of my “must have” tools.
- Firebug
- YSlow for Firebug
- Litmus
- Live HTTP Headers
- Screengrab!
- User Agent Switch
- Web Developer
- DOM Inspector
- Aardvark
- UltraEdit
- UltraCompare
Have any “must have tools” not on my list.

You might want to include something to put the pages up onto the internet like FileZilla.
UltraEdit is very nice but a little pricey, there’s also Notepad++ for those on a tighter budget.
Firebug is definitely the Macgyver knife of web page inspection, so much so that it makes some of the others in your list a little redundant.
One other tool that is a must have in my toolbox is FastStone Image Viewer for quick image editing, sizing and organizing.
Excluding that list, I use & abuse SciTE ( http://www.scintilla.org ) for coding.
And of course, Adobe Photoshop. I use Linux (Ubuntu) for everything web development wise, except for when I use Photoshop. I’ve never been able to get used to Gimp, unfortunately.
One big swiss knife for me is Pspad (www.pspad.com), I really recommend it for text-editing.
For a notepad replacement when UltraEedit isn’t needed I use Notepad2. I didn’t want to give up bookmarking, so I stay with the older version. The other one I couldn’t live without is Winmerge (haven’t tried UltraCompare, Winmerge is too good).
-Rich