Level 48

Total Experience Required 544,866

Level 100 progress: 7.98%

This is roughly the same as:

Killing 909 people in Warzone, or...
Killing 927 people in Execution, or...
Killing 770 people in Wingman, or...
Scoring 194,595 points in Guardian, or...
Scoring 592,246 points in Annex, or...
Scoring 358,465 points in Submission.

Horde (TU4)

Completing 1,363 waves on Casual, or...
Completing 909 waves on Normal, or...
Completing 682 waves on Hardcore, or...
Completing 545 waves on Insane.

Or a combination of the above. Have fun!