HTTP Status Codes in Real Use: What 200, 301, 404 and 500 Mean and When You See Them
When a website shows an error, the three-digit number tells you roughly why. The first digit alone shows which side the problem is on.
Reading the first digit
- 1xx: informational.
- 2xx: success.
- 3xx: moved elsewhere (redirect).
- 4xx: the request was wrong, such as 404 not found.
- 5xx: the server itself failed, such as 500.
Using the table
Type a number such as 40 or a word such as redirect or timeout to filter, or filter by class. Meanings are given in English and Thai.
Common examples
- 301 moved permanently, used when a page changes address.
- 403 forbidden, different from 401 where you have not yet identified yourself.
- 503 service temporarily unavailable.
Works offline
Once the page has loaded, the table needs no internet connection.