A great, Precision Screen Tool!

Rulers is an application that lets you measure, align and inspect everything on your monitor(s). It's available for both Mac and Windows systems.

"Rulers" allows you to create rulers on the entire screen area like most common graphic editors allow on their working areas only.

The guide lines enable you to measure and position objects with precision. Rulers is incredibly useful in many fields, such as computer graphics, desktop publishing and web design.

Rulers can also be used to select a screen area and take a screenshot that is automatically saved to your desktop or copied to system clipboard.

See Rulers in action

Main features

Unlimited rulers creation

Auto measure

Multiple units of measurement support

Multi monitor support

Take a screenshot of selected area or whole screen

Magnifier

Color picker

Automatic internet update

New auto measure feature

Available for both Mac OS X and Microsoft Windows

Available in 10 languages (English, Italian, Spanish, German, French, Japanese, Hungarian, Dutch, Russian, Czech)

What users say

Computernaut on MacUpdate.com:

This is the best screen ruler I've ever seen. Just like its product name, Rulers is free of any uncertainties as for what it can do, or can not do. No unnecessary bloat here.
Compared to similar tools that I've tried, I find that Rulers is the only app worthy of being called a real pixel scalpel.
Can't say for how long I've been waiting for exactly this app, but it's been long enough to say: Finally, you did it!

bitnix on iusethis.com:

I completely love this app.
No matter how simple it may look, compared to the other competitors, this app finally makes me feel SURE, that the pixels I measure, actually ARE the pixels that I intended to measure, so to speak.
Rulers manages to Keep It Simple™, and for that, I'd like to say thanks to the developers, omnidea. You rule! ;)

WhiteDog on Versiontracker.com:

Indeed, this is one of those "why didn't they think of it sooner" kind of applications. Instead of moving an on-screen ruler to try to measure a space onscreen, you can pull out guides just as you do in a graphics or layout program, which makes alignment much easier.

Mericoos on Versiontracker.com:

Rulers does a great job of providing on-screen guides, allowing the insertion of horizontal, vertical and intersection rules. It also gives you Photoshop-style rulers at the top and side of your screen for positioning. A HUD provides mouse coordinates and a magnifying glass, with two minimal views and one that shows all of the data at once.
This app provides screenshot capabilities and it also has an auto-measure tool. This is infinitely useful for quickly determining the pixel size of any on-screen area of which it can discern the edges. When Rulers is in the foreground, pressing Command-K will instantly show cross-hairs and a measurement for the area surrounding the mouse cursor.
Rulers is pretty darn useful, especially for web designers, and it's available for both Mac and Windows.

Natuzzone on MacUpdate.com:

I've recently discovered Rulers and I think it's a great tool. It's the easiest way to measure everything is on the screen and take screenshots.
The interface is simple and cool. Rulers can be created and moved both thru drag and drop and shortcut (making adjustments more accurate).
I'm using it on a dual monitor configuration, with different size monitors, and it works perfectly.

MacUtilidades on Twitter

Excelente app para quem está no mundo do design..

Cullenw on Twitter

Think I finally found that perfect Mac color picker app I have been looking for.

dspook on iusethis.com:

Me heart this app. Great for fine-tuning CSS layouts and such. Thanx Omnidea!

System Requirements: Mac OSX 10.4 or later.

Click to Developer's Site for more info.
Omnidea on Twitter