Thanks to kx365 we have the dopdf.com website available in Chinese Simplified too: dopdf.com/cn/. That brings the number of languages dopdf.com is available in to 24, thanks to all the translators that helped us!
If you want to help us translate the website (or the interface) in a language that's not yet translated in, you can start by visiting this page: Languages. You'll see there in which languages doPDF is not translated, and if you want to help you'll simply have to email us and we'll reply with details. Practically the website has about around 1200 words that need to be translated.