He played college football for the Oklahoma Sooners, where he was named the 2018 Big 12 Special Teams Player of the Year, and was selected by the Cleveland Browns in the fifth round of the 2019 NFL draft.

Seibert has also been a member of the Cincinnati Bengals, Detroit Lions, New York Jets, and New Orleans Saints.

He made his NFL debut in the Browns' 2019 regular season opener against the Tennessee Titans.

[10] Seibert was waived by the Browns on September 14, 2020, after missing a field goal and extra point in a 38–6 loss to the Baltimore Ravens in Week 1.

[12] Seibert played in four games during the 2020 season with the Bengals making six of nine field goals and all eight of the extra points he attempted.

[13] He was waived on August 31, 2021, after losing out the starting kicker job to Evan McPherson in training camp.

[20] On September 16, 2023, Seibert was signed to the New York Jets practice squad following an injury to kicker Greg Zuerlein.