All 13 Welsh counties are now available on 1911census.co.uk:
These records contain a total of over 2.4 million individuals, and over a million households.
Search for your Welsh ancestors on the 1911 census now
As the 1911 census is the first where household schedules were preserved, you will find that some of the census returns are printed and completed entirely in Welsh, while some are written in a mixture of Welsh and English. To help those who are not native Welsh speakers, there is a site section of useful tips, and translation tables to help you translate the most common Welsh census terms into English.
Common surnames and occupations
The tips will also help you narrow down your search results if you happen to have an ancestor with one of the most frequently occuring names, such as Jones or Evans, or one who worked in one of the dominant industries such as farming or coal mining.
Good luck with your Welsh research.