The injury-prone former Real Madrid and England defender, 31, left Tottenham last month after his contract at White Hart Lane expired. He has made just four Premier League appearances in the last two seasons.
Woodgate had been linked with a move back his first club, Leeds, but he has opted to continue his career in the Premier League with Stoke.
Fresh start: Jonathan Woodgate will attempt to relaunch his career at Stoke
He said: 'It was important for me to work hard on my fitness during the summer because I wasn't sure where I would be playing and I knew that would decide my future.
'So hopefully I can stay fit now because I feel I still have a lot to offer at this level.
'With the back-up from the medical and sports science department which they have here at Stoke, that can only help my prospects of doing that.
Lifeline: Jonathan Woodgate has a chance to resurrect his injury-plagued career
'I was thrilled when Tony Pulis askedme to come and join the club. I'd spoken to him a couple of times aboutthe progress that Stoke have made over the past three seasons and his plans for the future in aiming to build on that success.'
Pulis added: 'The lad is a top class player and it's been well documented that he has had his injury troubles, but we believe that if his fitness is managed properly, he will play games for us.
'We know that other Premier League clubs were keen on signing Jonathan, so we are delighted he has chosen us. It's a chance we are taking, but one we were keen to take because ofthe stature and quality of the player.'
Carling Cup winner: Woodgate scored the winner in the final against Chelsea in 2008
He added: 'We've effectively taken him on a pay-as-you-play deal which just shows how desperate the lad is to get his career back on the right track.'
Woodgate will link up with his new team-mates later this week when they return from their pre-season training camp in Austria.
Proven pedigree: Woodgate had a spell with Real Madrid
Stoke's chief executive Tony Scholes added: 'There is no doubt that we have acquired a player with outstanding quality and experience but he is one who has clearly struggled with injuries over the past two years.'
'However,sometimes a fresh start can trigger a change of fortunes. Jonathan has been working very hard throughout the summer on his fitness so he is desperate to make the most of this opportunity and to play in the Premier League.'
Woodgate, who has also played for Newcastle United and Middlesbrough, won eight international caps, the first of which came back in Kevin Keegan's reign in 1999 while he was at Leeds. His fine form for hometown club Middlesbrough earned him a recall in February 2007.
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