Effective maximum mailto: body lengths
There is a maximum length for the text in the &body section of a mailto: link. According to one of my co-workers, the W3C publish the limit as 256 (I don't have a link to back this up, though).
We're embedding mailto: links in both an e-mail and a webpage and have successfully used more than 256 characters. After a certain point, though, e-mail clients and browsers start flaking out and refusing to open the link.
I would like to know the actual maximum lengths allowed for the following:
Mail clients:
- Outlook (2003, 2007, 2010)
- Eudora (7.1, and/or whatever the latest version is)
- Thunderbird (latest version)
Browsers:
- Firefox (3+)
- IE (6, 7, 8)
- iPhone browser
Any and all numbers you can provide will be gratefully received.
Answer
The standard doesn't define a maximum length, leaving implementation up to browsers and mail clients (See IETF RFC 2368).
Microsoft products do have set limits:
- IE GET limit is 2,083 http://support.microsoft.com/kb/208427
- Outlook express: 456 characters http://support.microsoft.com/kb/q182985/
Other browsers are likely to work up to lengths beyond that of a reasonable email body. The iPhone doesn't have a documented limit, but works with up to 1MB of text.
Modern browsers that support data urls (everything except IE<9) should be fine.