Zamzar is a very famous site where you can convert files from one format to other free of size.This site is very famous and has some reputation for converting files from one format to another.All you need to do is.
1) Select the convert files tab and then upload the file which you want to convert.the file size should be less than 100 MB.
2) The next step is click on the drag drop and select the format in which you would like to convert the file.
3)The third step is you need to enter your E-mail address so that the converted file will be sent to your mail address.
4)The final step is press convert button so that the conversion takes place ans the converted document is sent to your mail addresses.
Some experts feel that Zamzar.com scan the entire document so be careful with what document your sending to them.Free users need not sign up.They provide contract services for bussiness people also.