HTTP (or HyperText Transfer Protocal) Status Codes are returned when a web server request is made by a website visitor, either human or non-human. These responses pass on the status of the web pages that are being requested.
What are HTTP Status Codes?
HTTP Status Codes are a 3 digit number returned by servers to indicate the status of a web element such as a web page.
One of the most important elements of the 3 digit number is the first digit as it denotes which category the status code refers to. There are 5 options, as follows:
- 100s – Informational: Request has been received and the process is continuing.
- 200s – Success: Request was received and processed successfully.
- 300s – Redirection: Request has been received, but needs to perform an additional step to complete the request.
- 400s – Client Error: Request was made by the client, but the page is not valid page.
- 500s – Server Error: Valid request was made by the client, but the server failed to complete the request.
There are a long list of HTTP Status codes.
Most Important Status Codes for SEO:
What is a 301 Moved Permanently status used for?
The 301 represents the best way of letting a search engine know you’ve most a page. The 301 redirect is important for SEOs as it passes through the link potency of the previous page.
What is a 302 Temporary Redirect used for?
This lets search engines know that the page has been moved temporarily and that the potency of the old page does not need to be passed through as it would with a 301.
When should I display a 404 page?
404 status response is used to let the search engine know that there is no element to be found at this location (often this can be doubled up with a 200 OK status response which lets the search engine know that this is normal), best practice is to have a dynamic 404 page which provides links to the most appropriate pages determined by the URL inputted.
What is a 503 Service Unavailable?
A 503 service unavailable response lets the search engines know when there is a temporary outage of the server due to routine maintenance or server overloading.
Which is the most important HTTP status code?
They are all important and you will get various arguments about which is the most important, however in most cases you can’t have one without another. My favourites are 301s because they let met control the link potency around the website and create extra strong pages and silo’d areas.
# March 16, 2010 at 7:56 pm
Great post, Thanks,
Im using this free HTTP testing tool to verify the HTTP status code return from the web when sending different HTTP Get or post:
http://soft-net.net/SendHTTPTool.aspx
# March 17, 2010 at 10:14 pm
Hi Jennifer,
Thanks for the comment I’ve had a look into the tool, great suggestion.
Simon.