As you gain experience points in Call of Duty: Black Ops, your rank will increase. There are 50 ranks in COD: Black Ops. Refer to the chart below to learn how much experience you need for each rank.
# Title EP
1 Private 1 0-299
2 Private 2 300-1199
3 Private 3 1200-2699
4 Private First Class 1 2700-4799
5 Private First Class 2 4800-7499
6 Private First Class 3 7500-10899
7 Specialist 1 10900-14999
8 Specialist 2 15000-19799
9 Specialist 3 19800-25299
10 Corporal 1 25300-31499
11 Corporal 2 31500-38599
12 Corporal 3 38600-46599
13 Sergeant 1 46600-55499
14 Sergeant 2 55500-65299
15 Sergeant 3 65300-75999
16 Staff Sergeant 1 76000-87799
17 Staff Sergeant 2 87800-100699
18 Staff Sergeant 3 100700-114699
19 Sergeant First Class 1 114700-129799
20 Sergeant First Class 2 129800-145999
21 Sergeant First Class 3 146000-163399
22 Sergeant Major 1 163400-181999
23 Sergeant Major 2 182000-201799
24 Sergeant Major 3 201800-222799
25 Lieutenant 1 222800-244999
26 Lieutenant 2 245000-268499
27 Lieutenant 3 268500-293299
28 Captain 1 293300-319399
29 Captain 2 319400-346799
30 Captain 3 346800-375499
31 Major 1 375500-405599
32 Major 2 405600-437099
33 Major 3 437100-469999
34 Lieutenant Colonel 1 470000-504299
35 Lieutenant Colonel 2 504300-539999
36 Lieutenant Colonel 3 540000-577199
37 Colonel 1 577200-615899
38 Colonel 2 615900-656099
39 Colonel 3 656100-697799
40 Brigadier General 1 697800-740999
41 Brigadier General 2 741000-785799
42 Brigadier General 3 785800-832199
43 Major General 1 832200-880199
44 Major General 2 880200-929799
45 Major General 3 929800-980999
46 Lieutenant General 1 981000-1033899
47 Lieutenant General 2 1033900-1088499
48 Lieutenant General 3 1088500-1144799
49 General 1144800-1202799
50 Commander 1202800+