Level 76

Total Experience Required 2,761,044

Level 100 progress: 40.45%

This is roughly the same as:

Killing 4,602 people in Warzone, or...
Killing 4,696 people in Execution, or...
Killing 3,900 people in Wingman, or...
Scoring 986,088 points in Guardian, or...
Scoring 3,001,135 points in Annex, or...
Scoring 1,816,477 points in Submission.

Horde (TU4)

Completing 6,903 waves on Casual, or...
Completing 4,602 waves on Normal, or...
Completing 3,452 waves on Hardcore, or...
Completing 2,762 waves on Insane.

Or a combination of the above. Have fun!