Wirify, the bookmarklet, turns any web page into a wireframe with one click. Wirify is free, easy and fun to use. To use it, drag the link from here to your bookmarks toolbar. You can also look here for details on How to install and update Wirify.
As said previously, Wirify is free. There is also Wirify Pro which gives you more options like exporting fully editable wireframes to Visio, OmniGraffle and Balsamiq – plus SVG for Illustrator and other applications. For getting Wirify Pro, you have to buy credits. Buying more credits is cheaper than buying single credit at a time. With Wirify Pro you can quickly do layout tweaks directly in browser and print wireframes in high resolution.
See examples of using wireframes created using Wirify. You can also read Wirify user guide and features.

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