Why GET method is faster than POST in HTTP?

Question

I am just new to web programming and just curious to know abt Get and Post methods of sending data from one page to another page.

It is said that Get method is faster than Post but i don't know why is it one reason i could find is that Get can take only 255 chars with it? Is there any other reasons , please someone explain me?

Answer 1

You should think of GET as "a place to go", and POST as "doing something". For example, a search form should be submitted using GET because the search result page is a "place" and the user will want to bookmark it or retrieve it from their history at a later date. If you submit the form using POST the user can only recreate the page by submitting the form again. On the other hand, if you were to perform an action such as clicking a delete button, you would not want to submit this with GET, as the action would be repeated whenever the user returned to the URL.

Answer 2

There are several misconceptions about GET and POST in HTTP. There is one primary difference, GET must be idempotent while POST does not have to be. What this means is that GETs cause no side effects, i.e I can send a GET to a web application as many times as I want to (think hitting Ctrl+R or F5 many times) and the requests will be 'safe'

I cannot do that with POST, a POST may change data on the server. For example, if I order an item on the web the item should be added with a POST because state is changed on the server, the number of items I've added has increased by 1. If I did this with a POST and hit refresh in the browser the browser warns me, if I do it with a GET the browser will simply send the request.

On the server GET vs POST is pure convention, i.e. it's up to me as a developer to ensure that I code the POST on the server to not repeat the call. There are various ways of doing this but that's another question.

To actually answer the question if I use GET or POST to perform the same task there is no performance difference.

You can read the RFC (http://www.w3.org/Protocols/rfc2616/rfc2616.html) for more details.

Answer 3

I agree with other answers, but it was not mentioned that GET requests can be cached while POST requests are never cached. I think this is the main reason for some GET request being performed faster. (Of-coarse this means that sometimes no request is actually sent. Hence it's not actually the GET request which is faster, but your browser's cache.)

HTTP Methods: GET vs. POST: http://www.w3schools.com/tags/ref_httpmethods.asp