Search sites typically do unit conversions in the address bar of your internet browser, so you do not need an antiquated conversion chart unless your PC is not handy. For example, say I want to convert 13/16" to mm, I would just type the following into the browser's address bar from DuckDuckGo.com:
13/16" to mm (or '13/16 in to mm')
Then press the Enter key or click Go, whichever you prefer to get the following:
Attachment 300751