Apple - How do I run the iPad simulator to test a website on my mac

Install XCode, then the simulator is located at /Applications/Xcode.app/Contents/Developer/Applications/Simulator.app Once it's running, go to Hardware -> Device, then pick the iOS version and device. It will boot up, then you can start Safari.

Update: XCode.app is now a package rather than a folder. In Finder, option/right click on XCode.app and select 'Show Package Contents', then follow the path down from there.

In recent versions of Xcode it can be found here:

/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneSimulator.platform/Developer/Applications/iPhone Simulator.app

In Xcode 6.1.1 (Yosemite & Mavericks) it can be found here:

/Applications/Xcode.app/Contents/Developer/Applications/iOS Simulator