how do I airdrop a file from my mac to my iPhone?

AirDrop system requirements

To send items to an iPhone, iPad, or iPod touch, or to receive items from those devices, you need a 2012 or later Mac model with OS X Yosemite or later, excluding the Mac Pro (Mid 2012).

To send items to another Mac, you need:

• MacBook Pro (Late 2008) or later, excluding the MacBook Pro (17-inch, Late 2008)
• MacBook Air (Late 2010) or later
• MacBook (Late 2008) or later, excluding the white MacBook (Late 2008)
• iMac (Early 2009) or later
• Mac Mini (Mid 2010) or later
• Mac Pro (Early 2009 with AirPort Extreme card, or Mid 2010)

Learn how to identify your model of MacBook, MacBook Pro, MacBook Air, iMac, Mac mini, or Mac Pro.

Use AirDrop to send content from your Mac - Apple Support