It reveals capital dwellers use one of the most frowned-upon four-letter words less than people in Glasgow and London in their tweets.
FBomb.co is an interactive map that drops a pin with a warning sign at any place in the world where a potty-mouthed tweet is posted.
Set up by Martin Gingras, a student at Carleton University in Ottawa, Canada, the site has been an instant hit.
It highlights a clear north-south divide in the UK and shows there is generally a far higher frequency of profanities from Glasgow-based Twitter users than those in Edinburgh.
The real-time map also shows that the greatest volume of vulgar tweets worldwide originate in the US and the UK.
Edinburgh University applied linguistics professor John Joseph has labelled FBomb “a very interesting site”.
He said: “In Scotland you can see a high density of swearing stretching from Glasgow across the Central Belt to Dunfermline. Our own research has found that swearing is a form of social bonding among friends and used more by those who are comfortable with long-established social ties.
“Edinburgh has more people coming and going than Glasgow. People don’t have the same fixed social ties. Also the stereotype of Edinburgh being a bit prim might have some accuracy to it.”
Professor Joseph said the offensive data gives experts an up-to-date map of people’s language they have never had before.
The map shows swearing clusters around sporting fixtures – such as Hibs v Hearts derbies – and that bad language gets more prevalent as the day goes on.
Most foul-mouthed tweets are posted in the late afternoon which the academic believes is especially interesting.
He believes this could be a signal that people become more angry as the day progresses, or it could be “an expression of joy as people may be excited about the work day ending or about a film they are going to go and see”.
The map – which captures the language used by such accomplished swearers as Trainspotting author Irvine Welsh, 55 – has become an instant cult hit.
Creator Mr Gingras, an aspiring software designer, said: “I’m surprised by how far it has spread. I did not expect to be able to generate that sort of interest. I do believe that the site merits the 30 seconds the average person spends on it as far as entertainment value goes.”
However, Scotland hasn’t always been as relaxed about the use of swear words. In medieval times, Scotland became the first country in the world to have a law against swearing, which was considered an offence against God. Passed by King Donald VI in 900 AD, swearing was punishable by the offender having their tongue burned out with a hot iron.