[{"emails":["aashby71@yahoo.com","alidsdvz@yahoo.com","alw100794@gmail.com","alysenhurt8@gmail.com"],"phones":["3331234451","3331234454","7423742992","1740742393","4321221133"]}]

db.collection.aggregate([{$project:{emails:{$size:"$emails"},phones:{$size:"$phones"}}}])