I quite often get asked (and ask myself) what is the best GANTT software for basic use.
Recently we have been comparing a few solutions so here are a couple of quick tips.
If you have a license for Microsoft Project I would use that, though it is a bit complex.
Online it is hard to find anything good which is free. Smartsheet.com is interesting and useful and has (basic) gantt functions, but you have to pay.
On the free, offline side:
lots of features, you can copy and paste from and to spreadsheets, but basically your export is best just as a screenshot. You can make an OK pdf, fit to page width or height and that is about it.
It can import MS Project and also Gnome Planner format, and can save in MS Project format.
The interface is a bit awkward (Java), to move tasks up and down you have to cut and paste. It has different constraint types which are useful for advanced users but can be awkward to resolve.
On Linux we have gnome planner - looks nice, easy to use. Export is html