There is a plugin I love so much especially for responsive design tools
Pendule can be found on google chrome extension https://chrome.google.com/webstore/detail/gbkffbkamcejhkcaocmkdeiiccpmjfdi
The features as described on google:
Extended web developer tools for Chrome. Use this extension in addition to the built-in Developer Tools (Ctrl+Shift+I). FEATURES ¯¯¯¯¯¯¯¯¯¯ ✔ View Selection Source added to Google Chrome's context menu ✔ View CSS (and beautify it!) ✔ Reload CSS ✔ Disable all styles ✔ Disable inline styles ✔ Disable embedded styles ✔ Disable linked style sheets ✔ Show used colors ✔ Show passwords ✔ Remove maxlength attributes ✔ Convert select elements to text inputs ✔ Show hidden elements ✔ Clear radio buttons ✔ Enable form elements ✔ Convert form methods ✔ View images information ✔ Hide all images ✔ Hide background images ✔ Show alt text, dimensions and paths ✔ View JavaScript (and beautify it!) ✔ View generated source (syntax highlighted code appears in a new tab) ✔ Display ruler ✔ Display color picker (the first that have been available since late 2009!) ✔ Topographic view ✔ Remove cookies from current site ✔ Display window and viewport size ✔ Resize your browser to various sizes ✔ Validate HTML ✔ Validate CSS ✔ Validate links ✔ Validate feed ✔ Validate accessibility (WAI) ✔ Validate local HTML ✔ Validate local CSS OPTIONS ¯¯¯¯¯¯¯¯ Right click the toolbar icon, and select Options for shortcuts and some options. ISSUES ¯¯¯¯¯¯¯ Disable JavaScript is missing? Star issue http://crbug.com/37762. PLEASE NOTE ¯¯¯¯¯¯¯¯¯¯¯¯¯ Any previously loaded pages need to be reloaded after the installation. Like the extension? Contribute by donating, spreading the word or at least rate it!
I hope you guys like this and see how this could help you.
Leave a comment to show how this has helped you 