W3C Validator Error Code Frequency List

Popularity	Error Code	Frequency
1	108	2,253,893
2	127	2,013,162
3	344	1,371,836
4	79	1,232,169
5	64	1,229,145
6	76	1,114,796
7	325	859,846
8	25	859,636
9	338	859,636
10	247	798,046
11	65	774,381
12	68	631,292
13	82	530,643
14	73	519,521
15	131	467,695
16	106	438,141
17	xmlw	406,311
18	70	340,145
19	63	266,663
20	141	209,212
21	394	180,861
22	66	178,258
23	123	159,982
24	403	159,477
25	404	147,508
26	139	137,600
27	257	120,604
28	105	118,366
29	53	117,979
30	112	105,046
31	78	102,736
32	187	95,174
33	81	84,347
34	74	82,933
35	410	74,703
36	125	73,308
37	no-x	67,931
38	62	67,358
39	111	60,084
40	121	56,101
41	122	53,822
42	163	49,169
43	246	46,457
44	55	41,668
45	31	31,674
46	107	29,353
47	407	29,097
48	38	22,545
49	185	20,452
50	137	19,928
51	248	12,904
52	183	12,743
53	42	11,142
54	109	8,843
55	46	8,480
56	388	8,231
57	387	7,674
58	28	5,270
59	154	5,159
60	47	5,065
61	323	4,868
62	100	4,424
63	61	4,060
64	50	3,184
65	8	2,569
66	337	2,539
67	253	1,980
68	115	1,446
69	102	1,426
70	378	1,326
71	249	1,275
72	143	1,237
73	334	1,212
74	306	1,171
75	333	1,058
76	162	958
77	wron	887
78	39	856
79	161	823
80	15	655
81	2316	633
82	164	543
83	22	536
84	67	468
85	32	466
86	400	416
87	60	304
88	16	278
89	117	197
90	380	192
91	83	182
92	188	140
93	189	99
94	379	87
95	359	86
96	243	85
97	357	85
98	360	85
99	361	85
100	362	85
101	372	85
102	381	85
103	382	85
104	384	85
105	385	85
106	393	85
107	395	85
108	396	85
109	397	85
110	48	69
111	254	68
112	252	63
113	250	54
114	43	45
115	398	45
116	44	39
117	2304	30
118	368	16
119	401	15
120	386	13
121	23	11
122	77	11
123	24	9
124	166	7
125	2311	7
126	412	6
127	9	5
128	13	5
129	40	5
130	51	4
131	6	2
132	389	3
133	45	1
134	140	1