Upgrade
HTTP response headerThe Upgrade header field is an HTTP header field introduced in HTTP/1.1. In the exchange the client begins by making a cleartext request which is later upgraded to a newer HTTP protocol version or switched to a different protocol.
Header usage statistics
Upgrade response header information and usage statistics.| Websites using header Upgrade | 858,043 |
| Percentage of websites that use Upgrade header | 7.36% |
| Total discovered header values | 64 |
| Header uses directives | No |
| Header values are unique or random | No |
| Most popular in the country | 
United States of America
|
Connected technologies
Technologies that utilize the header
HTTP/2, category
Miscellaneous, total
858,010 websites
|
Distribution by websites popularity
Upgrade detection in the top websites by popularity| Top 10k sites | 290 websites |
| Top 100k sites | 7,437 websites |
| Top 1m sites | 93,326 websites |
Websites utilizing Upgrade
List of websites that use Upgrade header| Domain | Country | Rank | Contacts |
|---|---|---|---|
|
|
Canada
|
11 | |
|
|
United States of America
|
322 | |
|
|
United States of America
|
636 | |
|
|
France
|
901 | |
|
|
France
|
901 | |
|
|
United States of America
|
934 |
Geographical Distribution
Header usage distribution by websites across the globe.Common header values
List of top common Upgrade header values| Header value | Value prevalence |
|---|---|
| h2,h2c | 74.88% |
| h2 | 24.28% |
| h2c | 0.67% |
| h2c,h2 | 0.11% |
| h2,http:/1.1 | 0.03% |
| h2,HTTP,1.1 | 0.00% |
| h2,http1.1 | 0.00% |
| h2,hc2 | 0.00% |
| http:/1.1 | 0.00% |
| HTTP/1.1 | 0.00% |
| h2,http/1/1 | 0.00% |
| h2 h2c http/1.1 | 0.00% |
| h2,h2c,HTTP/1.1 | 0.00% |
| h2,h2c,http/1.1​ | 0.00% |
| h2,h2c,http:/1.1 | 0.00% |
| h2,h2c,h2-14 | 0.00% |
| h2,http | 0.00% |
| h2,http1/1 | 0.00% |
| hc,h2 | 0.00% |
| h2,,h2c, | 0.00% |