These are a list of common port number on which web applications are hosted usually. One can send probes to these port numbers and check whether a particular web service is running on them or not.

common-web-ports.txt

21
22
25
80
110
135
143
261
271
324
443
448
465
563
614
631
636
664
684
695
832
853
854
990
993
989
992
994
995
1129
1131
1184
2083
2087
2089
2096
2221
2252
2376
2381
2478
2479
2482
2484
2679
2762
3077
3078
3183
3191
3220
3269
3306
3410
3424
3471
3496
3509
3529
3539
3535
3660
36611
3713
3747
3766
3864
3885
3995
3896
4031
4036
4062
4064
4081
4083
4116
4335
4336
4536
4590
4740
4843
4849
5443
5007
5061
5321
5349
5671
5783
5868
5986
5989
5990
6209
6251
6443
6513
6514
6619
6697
6771
7202
7443
7673
7674
7677
7775
8243
8443
8991
8989
9089
9295
9318
9443
9444
9614
9802
10161
10162
11751
12013
12109
14143
15002
16995
41230
16993
20003