by Kev Geoghegan
Radio 1 music reporter
Duffy performed at Glastonbury in June
Duffy has become the biggest selling UK artist of the year so far.
Sales of her debut album, Rockferry, have now passed the one million mark in the UK since its release in March.
She has sold 2.5 million records worldwide and is now certified gold in fifteen countries, including the US and is platinum in a further ten.
Duffy's about to head off to the States for a string of gigs but admits she finds it hard to believe that Americans are starting to recognise her.
She said: "I dont know if I'm well known over there but I did hear my song on the radio which was really weird.
"It's an exciting time for me but who knows?"
After festivals shows at Glastonbury and Wakestock in her native Wales, Duffy is also set to play the V festivals in Chelmsford and Staffordshire on 16-17 August and the Hydro Connect festival in Scotland on 31 August.
It's also being reported that she is in line to record the theme song to the next Bond movie.
Duffy releases her new single Stepping Stone on 1 September.