Level 50

Total Experience Required 625,387

Level 100 progress: 9.16%

This is roughly the same as:

Killing 1,043 people in Warzone, or...
Killing 1,064 people in Execution, or...
Killing 884 people in Wingman, or...
Scoring 223,353 points in Guardian, or...
Scoring 679,769 points in Annex, or...
Scoring 411,439 points in Submission.

Horde (TU4)

Completing 1,564 waves on Casual, or...
Completing 1,043 waves on Normal, or...
Completing 782 waves on Hardcore, or...
Completing 626 waves on Insane.

Or a combination of the above. Have fun!