Level 83

Total Experience Required 3,756,493

Level 100 progress: 55.03%

This is roughly the same as:

Killing 6,261 people in Warzone, or...
Killing 6,389 people in Execution, or...
Killing 5,306 people in Wingman, or...
Scoring 1,341,605 points in Guardian, or...
Scoring 4,083,145 points in Annex, or...
Scoring 2,471,377 points in Submission.

Horde (TU4)

Completing 9,392 waves on Casual, or...
Completing 6,261 waves on Normal, or...
Completing 4,696 waves on Hardcore, or...
Completing 3,757 waves on Insane.

Or a combination of the above. Have fun!