Brit Slang Guide (only a few I didn't know)
British Slang 1/3
Essential Guide to British Slang
UK english/american-Some of these aren't accurate, but it's pretty neat!
Some differences between American and British English for you. British left and American right. Im going to start speaking British slang.
British Vs American English: 100+ Differences Illustrated: I seriously need to keep this on hand, because I can never remember which spelling to use for some of these words
British Slang 2/3
Top 100 Most Beautiful British Slang Words and Phrases - Guide to English Slang - Anglotopia.net
Guide to British Slang – Earthly Mission