Level 62

Total Experience Required 1,330,651

Level 100 progress: 19.49%

This is roughly the same as:

Killing 2,218 people in Warzone, or...
Killing 2,264 people in Execution, or...
Killing 1,880 people in Wingman, or...
Scoring 475,233 points in Guardian, or...
Scoring 1,446,360 points in Annex, or...
Scoring 875,429 points in Submission.

Horde (TU4)

Completing 3,327 waves on Casual, or...
Completing 2,218 waves on Normal, or...
Completing 1,664 waves on Hardcore, or...
Completing 1,331 waves on Insane.

Or a combination of the above. Have fun!