What are the minimum system requirements for Office 365?

Microsoft Office 365 needs the following system requirements to operate effectively.

Browser Windows Internet Explorer 8, 9, or 10 
Mozilla Firefox 10.x+ 
Apple Safari 5 (Mac) 
Google Chrome 17.x
Email client software Outlook 2010 with Service Pack 1 
Outlook 2007 with Service Pack 3 
Entourage for Mac 2011 with Service Pack 3
Computer and processor 1 GHZ or faster x86 or 64-bit processor with SSE2 instruction set
Memory 1 GB RAM (32-bit) 
2 GB RAM (64-bit) recommended for graphics features, Outlook Instant Search & certain advanced functionality
Disk space 3 gigabytes (GB)
Monitor resolution 1024 x 768
Mobile devices Exchange ActiveSync must be supported for Office 365 
Operation system Office 2013 requires either Windows 7, Windows 8 or Mac OSX
Using Outlook Web App on smartphones and tablets For the best experience use the integrated web browser of these devices, Windows 8 tablet, iOS 6 or later versions for iPhone4s or later versions or iOS 6 or later versions for iPad2 or later versions

For complete details, please refer to the Software requirements for Office 365 for business page