Common HTTP Error Codes & Troubleshooting

Whenever you access an application over the internet or intranet, every HTTP request sent to a server gets a response with a status code. These codes are three-digit numbers grouped into different classes:

• 1xx (Informational)
• 2xx (Success)
• 3xx (Redirection)
• 4xx (Client Error)
• 5xx (Server Error)

The first digit of a status code quickly identifies its class. This article focuses on the most commonly encountered HTTP error codes - mainly 4xx and 5xx codes - and tips for troubleshooting them.

Common HTTP Error Codes​

S.No	Status Code	Name
1	400	Bad Request
2	401	Authorization Required
3	402	Payment Required
4	403	Forbidden
5	404	Not Found
6	405	Method Not Allowed
7	406	Not Acceptable
8	407	Proxy Authentication Required
9	408	Request Timeout
10	409	Conflict
11	410	Gone
12	411	Length Required
13	412	Precondition Failed
14	413	Request Entity Too Large
15	414	Request URI Too Long
16	415	Unsupported Media Type
17	416	Request Range Not Satisfiable
18	417	Expectation Failed
19	422	Unprocessable Entity
20	423	Locked
21	424	Failed Dependency
22	500	Internal Server Error
23	501	Not Implemented
24	502	Bad Gateway
25	503	Service Unavailable
26	504	Gateway Timeout
27	505	HTTP Version Not Supported
28	506	Variant Also Negotiates
29	507	Insufficient Storage
30	510	Not Extended

Tip:
If you encounter any HTTP error codes not mentioned here, feel free to discuss them in the comments below! Sharing your experience can help others troubleshoot issues faster.