Tools I use all the time

Since I started making websites, I have been building up a list of useful tools, scripts, and other bits of software that just make my job a little bit easier. This is my current list.

Color Scheme Designer 3
An invaluable tool for finding complementary shades and colours, with a good range of options and a simple interface.
CSS Lint
A controversial choice, but still something I use regularly. You don’t have to do everything it says, but it will pick up errors and it might just make your code a bit more efficient. Always read the label.
Current IP Check
Does exactly what it says it does.
DomainTools WHOIS Lookup
There are plenty of options for WHOIS queries, but I have always found this one the quickest and simplest.
Down For Everyone Or Just Me
Also available at isup.me, this simple site will save a lot of shouting across the office.
Dynamic Dummy Image Generator
Have you ever needed a dummy image to fill a gap in hurry? This generator is quick and simple and even prints the dimensions on the image, so you can remember what they are later.
Font Squirrel
Not really a single tool, this is a great resource for finding open source web fonts. The brilliantly flexible @font-face generator has also made a lot of projects a lot easier.
HTML Lint
You know your code is valid, but is it pretty?
htpasswd generator
If you don’t have time to do it yourself, this can quickly add a bit of security to your site.
Is My Blog Working?
This site checks your blog for errors, efficiency, and visibility. More useful than you might think.
JSHint
A friendlier cousin of the venerable JSLint, this code checker has plenty of options and provides really useful feedback on your JavaScript code.
Mr Data Converter
What if you have some comma-delimited data that need to be in an HTML table, or a PHP array, or a JSON string, or something else entirely? Job done.
PXtoEM.com
Put away the calculator. This site converts your old-fashioned px units to shiny, responsive em units.
Responsive Design Test Bookmarklet
Still endlessly resizing the window to test your responsive design? Stop that. You can also use Matt Kersley’s version, but personally I find the bookmarklet more convenient.
Validator.nu
The original and best HTML5 validator.

And that is my list.