Extensions can be enabled or disabled on the fly in Google Chrome without the need of restarting the browser (which is the case for Firefox). This makes it very easy for you to give the following extensions a try. If you are not already using these plugins, go ahead and give them a try. You might find some of them useful for your needs.
1. Measure It!
Measure It enables you to draw out a ruler that will help you get the pixel width and height of any elements on a webpage.
2. IE Tab
Yes! There is an extension to use Internet Explorer within Chrome. This is a Windows-only extension and you can use it to render those web sites which work only when using IE. It can double up as a great extension to test the behaviour of your website when using IE.
3. Firebug Lite
Firebug Lite is not a substitute for Firebug, or Chrome Developer Tools. It is a tool to be used in conjunction with these tools. Firebug Lite provides the rich visual representation we are used to see in Firebug when it comes to HTML elements, DOM elements, and Box Model shading. It provides also some cool features like inspecting HTML elemements with your mouse, and live editing CSS properties.
4. Speed Tracer
5. Eye Dropper
Eye Dropper is extension for Google Chrome and Chromium. It allows you to pick color from any webpage or from advanced color picker. It is great tool for web developers.
6. Lorem Ipsum Generator
Chrome Extension that generates random “Lorem Ipsum” text. It uses a minimalist and well looking design.
7. Resolution Test
An extension for developers to test web pages in different screen resolutions, with an option to define your own resolutions.
8. Pendule
Pendule provides extended web developer tools for Chrome.
9. Aviary Screen Capture
This quick screen capture extension is a must-have for bloggers and designers alike! It will perform a screen capture of the visible portion of any webpage and then open the capture instantly in a basic image editor where you can do markup (draw arrows and rectangles), edit (crop, rotate and resize) and get the exact pixel colors of the image. A perfect companion tool for designers and bloggers!
10. Chrome Sniffer
This extension will help web developer to inspect web framework / CMS and javascript library running on current browsing website. An icon will appear on address bar indicates the detected framework.
11. Chrome SEO
The Google Chrome SEO Extension provides easy access to Search Engine Optimization Tools that can help you with Competitive Analysis, Keyword Research, Backlink Checks, PageRank Checks and other daily SEO tasks.
12. Validity
Validity can be used to quickly validate your HTML documents from the address bar. Just click the icon in the address bar to validate the current document without leaving the page. The number of validation errors can be seen in the tool tip and the detail can be seen in the JavaScript console.
13. Meta SEO Inspector
Meta data is not just the usual HTML meta tags, but the XFN tags, various microformats, the recently introduced canonical attribute, the no-follow links and so on.
This extension is mainly aimed at web developers that need to verify the description tag of their site to follow the Webmasters’ Google Guidelines, SEO, or even to who is curious about page contents that are usually not visible, but can reveal interesting site properties.
14. Web Developer
Adds a toolbar button with various web developer tools. The official port of the Web Developer extension for Firefox.
15. Chrome Web Developer Tools
Chrome Web Developer Tools aims to replicate the features available in the popular Firefox add-on called Web Developer.
16. Color Picker
Quickly get the Hex and RGB values of any color! Also adjust Hue, Saturation, and Balance.
17. Image Cropper
This extension help you to crop any images on the fly. It’s especially useful when you need to crop your online album photo for IM thumbnail.
18. Picnik for Chrome
The Picnik Extension for Chrome lets you easily edit the images you come across while browsing the web. With a click you can create a snapshot of your current web page and open it in Picnik for easy editing, annotation and sharing. Do the same for all the image on the current page — just pick the image from the dynamic hot list and then edit, annotate and share with Picnik.
19. BuiltWith
BuiltWith is a web site profiler tool. Upon looking up a page, BuiltWith returns all the technologies it can find on the page. BuiltWith’s goal is to help developers, researchers and designers find out what technologies pages are using which may help them to decide what technologies to implement themselves.
20. iMacros
iMacros was designed to automate the most repetitious tasks on the web. If there’s an activity you have to do repeatedly, just record it in iMacros. The next time you need to do it, the entire macro will run at the click of a button! With iMacros, you can quickly and easily fill out web forms, remember passwords, create a webmail notifier, and more. You can keep the macros on your computer for your own use, use them within bookmark sync / Xmarks or share them with others by embedding them on your homepage, blog, company Intranet or any social bookmarking service as bookmarklet. The uses are limited only by your imagination!
21. Snippy
Snippy allows you to grab snippets of web pages, save them for future use and upload them to Google Docs. Snippy capture rich contents and preserves formatting, so you can capture paragraphs, images, links and more.
22. JavaScript Tester
This extension adds a small & useful shortcut to your browser “Alt+J”. To run and test performance of JavaScript code.
23. csscan
Inspired by the Firefox Extension CSSViewer, this Chrome extension allows you to easily scan an element’s basic CSS properties without having to delve into the inspector window.
24. MultiSwitch
Switch between development, test and productive application.
25. Regular Expression Checker
This extension is a simple regular expression testing tool for Chrome.
26. jsshell
jsshell is a small command window placed at the bottom of your Chrome browser that lets you run jQuery and jLinq commands no matter what page you’re on!
27. JSONView for Chrome
JSONView for chrome is an extension that helps you to parse and view JSON documents.
28. PHP Documentation
Makes it simpler to search the PHP reference manuals by providing an icon in the toolbar.
29. XML Tree
Displays XML data in a user friendly way.
30. View Selection Source
View selection source in resizable popup. Drag the bottom right corner to resize. Simple, but very useful for web developers.