He played college football for the Stanford Cardinal, earning unanimous All-American honors in 2012 before being selected by the Philadelphia Eagles in the second round of the 2013 NFL draft.

He holds the NFL record for most receptions in a season by a tight end and has also been a member of the Arizona Cardinals and Detroit Lions.

[12] On January 8, 2013, Ertz announced, through a statement released by Stanford, his decision to forgo his senior season and enter the 2013 NFL Draft.

[14] On March 24, 2013, Ertz attended Stanford's pro day and opted to perform some of the drills again in an attempt to shorten some of his times and increase his vertical and broad jump.

He was ranked the second best tight end prospect in the draft by Sports Illustrated, DraftScout.com, SBNation, and NFL analysts Mike Mayock, Mel Kiper, and Rob Rang.

[10] He was the second tight end drafted behind Notre Dame's Tyler Eifert, but ahead of future Pro Bowlers Travis Kelce and Jordan Reed and fellow Stanford teammate Levine Toilolo.

[22] Head coach Chip Kelly explained the selection of Ertz and his plan to use three-tight end sets that had been successfully used by the New England Patriots.

Head coach Chip Kelly named Ertz the third tight end on the depth chart to begin the regular season, behind Brent Celek and James Casey.

[28] On September 29, 2013, Ertz earned his first career start after surpassing James Casey on the depth chart and was designated as the top receiving option at tight end.

[30] On December 1, 2013, Ertz made five catches for a season-high 68 receiving yards and two touchdowns during a 24–21 win against the Arizona Cardinals in Week 13.

[35] On January 4, 2014, Ertz appeared in his first career playoff game and made three receptions for 22 yards and caught a seven-yard touchdown pass from quarterback Nick Foles in the Eagles' 26–24 loss to the New Orleans Saints in the NFC Wild Card Round.

On November 22, 2015, Ertz caught two passes for 12 yards before exiting the Eagles' 45–17 loss to the Tampa Bay Buccaneers in the second quarter after sustaining an injury.

[43] During the course of the play, he caught a pass from quarterback Mark Sanchez, hurdled cornerback Sterling Moore, and was immediately hit by linebacker Lavonte David.

[44] On December 22, 2015, Ertz caught a season-high 13 passes for 122 receiving yards in the Eagles' 38–24 loss to the Washington Redskins in Week 16.

[45] On December 29, 2015, the Philadelphia Eagles fired head coach Chip Kelly after their loss to Washington left them with a 6–9 record.

Offensive coordinator Pat Shurmur was named interim coach for the season's final game,[46] a 35–30 victory at the New York Giants in which Ertz had nine receptions for a career-high 152 yards.

[52] On December 12, 2016, Ertz made ten receptions for 112 receiving yards in the Eagles' 27–22 loss against the Washington Redskins in Week 14.

[63][64] On December 3, 2017, Ertz caught two passes for 24 yards before exiting the Eagles' 24–10 loss at the Seattle Seahawks in the third quarter after sustaining a concussion while attempting to make a catch that was defended by Bradley McDougald.

[69] The Philadelphia Eagles finished atop the NFC East with a 13–3 record, clinching a first round bye and home-field advantage.

[71] On January 21, 2018, Ertz made his first career start in the playoffs and caught eight passes for 93 yards during a 38–7 victory against the Minnesota Vikings in the NFC Championship.

During the fourth quarter, he caught the go-ahead touchdown reception on a seven-yard pass by Nick Foles, after beating safety Devin McCourty on a slant route, to put the Eagles up 38–33.

[78] After another touchdown in a win over the New York Giants, a Week 7 loss to the Carolina Panthers saw Ertz record nine receptions for 138 receiving yards.

[80] During the Eagles' Week 16 win over the Houston Texans, Ertz broke Jason Witten's NFL record for most receptions by a tight end with 113.

[89] In Week 14 against the New York Giants, Ertz caught nine catches for 91 yards and two touchdowns, including the game winner, which sealed a 23–17 overtime win for the Eagles.

[96] Ertz was traded to the Arizona Cardinals on October 15, 2021, in exchange for cornerback Tay Gowan and a fifth-round selection in the 2022 NFL draft.

[108] In the Week 17 win over the Atlanta Falcons, Ertz recorded six receptions for 72 receiving yards and two touchdowns, including the game-winning score in overtime that clinched the Commanders' playoff berth.

[116] On February 26, 2016, Ertz proposed to professional soccer player Julie Johnston, then a starting defensive midfielder for the U.S. women's national team, at Klein Field, the Stanford University baseball stadium where they first met.