URL character limit for get requests
Here is an excerpt on URL length limitations for Internet Explorer; use it as a baseline (certain browsers such as Opera support longer URLs):
"Microsoft Internet Explorer has a maximum uniform resource locator (URL) length of 2,083 characters. Internet Explorer also has a maximum path length of 2,048 characters. This limit applies to both POST request and GET request URLs. If you are using the GET method, you are limited to a maximum of 2,048 characters, minus the number of characters in the actual path.
However, the POST method is not limited by the size of the URL for submitting name and value pairs. These pairs are transferred in the header and not in the URL. RFC 2616, "Hypertext Transfer Protocol – HTTP/1.1," does not specify any requirement for URL length."
Here is an article about the HTTP browser limit on the Microsoft website:
You can use TinyURL to extend this length.
URL character limit outside Internet Explorer
If you consider browsers other than Internet Explorer, then the next limit you run into is the Content Delivery Network HEADER limit. If the URI size exceeds 4 K, the server generates a 4xx/5xx error, depending on the environment.
In summary, Adobe's Content Delivery Network standards are depicted below:
- Max URI: 4796 bytes (for everything including query string, but not the protocol or host name, which are not normally in the URI line. If protocol and host name appear in the URI line, they count toward the total URI bytes)
Max Request Size (remote client): 16 K (baseline controllable)
- Max request Size (localhost): 124K-1 (not baseline controllable)
- Max header name: 64K-1 (relevant only on localhost requests)
- Max header value: 64K-1 (relevant only on localhost requests) The request message body (POST entity) is controlled by the normal documented mechanisms.
- Max Response Headers: 8190 bytes