Transition your beautiful design mockup to look completely the same to your HTML and CSS, it can be a real nightmare sometimes. Making a pixel perfect layout, takes time and patience.
There’s a great tool I found for this, it’s called Pixel Measure. This is a photoshop plugin that measures your pixels in seconds, installation requires 2 minutes and you are ready to rock on your html layouts.
To install the plugin, you just drop the file on your photoshop directory to the scripts folder, then you restart the program. Make sure your script installed correctly on the menu File under Scripts.
I highly recommend to add a keyboard shortcut for this script. You can set this under Edit and then Keyboard Shortcuts menu. Now, the only thing you need to do is to click on your marquee tool and then press the shortcut that you configured previously.
Thanks to Nikola to make this script possible. Hope it helps for your future work.