I just want to make sure which browsers send the Expect: 100-Continue header? So that until the server responds with a 100 Continue HTTP status, no data should be sent.

  • This is unclear. Could you elaborate? – Itai Mar 2 '13 at 2:14
  • @Itai, There is special header in HTTP called Expect 100 Continue. When a browser send this header until server returns 100 continue, client will not send any data to server – user960567 Mar 2 '13 at 8:00
  • Just to clarify... the browser sends an Expect: header with a value of 100-Continue, the server then responds with an HTTP status code of 100 Continue if applicable. I don't think any browser sends this header automatically, this is down to your code - IMHO. – MrWhite Mar 2 '13 at 18:00