wkhtmltopdf - cannot convert local file

You need to provide the full path. Using file:/// does not make use of the current working directory. Rather, it specifies the path to the file from the root of the file system.

Try with this option :

wkhtmltopdf --enable-local-file-access

It works for me.

Just as a notice to any future people. I couldn't get the accepted answer working on Ubuntu 14.04, so I resorted to piping my HTML to the wkhtmltopdf command like so:

cat test.html | wkhtmltopdf - test.pdf

This is from the wkhtmltopdf command-line help:

Use - for stdin or stdout