It was the Australian Red Bull driver's 11th career pole position, and it will be the second time this year that he will have started from the first slot, after inheriting the position from Michael Schumacher in Monaco in May.
"The lap was very good apart from Turn 15," Webber said. "I got in OK but the exit was not great.
"Apart from that it worked well because I got [Turns] 11 and 12 absolutely as good as I could, so you take the rough with the smooth. But it was a tight session for all of us - scrubbed tyres, new tyres, Fernando [Alonso] did a reasonable lap on the scrubbed.
"That is the way it is with the Pirellis, things can move around quite a bit."
Webber lost most of the final free practice session to a software glitch that prevented the team from firing up his engine. It meant that it was not possible for him to do a qualifying simulation.
Nevertheless Webber said that Red Bull was quietly confident that another front-row lockout would be possible.
"We didn't get to run anywhere near what we like to in P3 and our information on the option [tyre] was limited," he said. "There was bit of catch up going on. I had not the best sector two or three in terms of balance issues and other things. That is what we focused on in Q3, so we got the job done.
"I think off the back of Suzuka we improved the car a bit," he added. "You never get ahead of yourself, but we were optimistic after that, though we knew it wouldn't be a given.
"We have a handy car and the guys are working very, very hard, no question. That hard work is paying off but we'll keep focused on ourselves and keep pushing the lap times down."