Korda had seven birdies in her second straight bogey-free round to reach 13 under on The Crossings course at the Robert Trent Jones Golf Trail's Magnolia Grove complex.
''I'm hitting the ball good, and I'm having a lot of fun out there,'' Korda said. ''I feel really comfortable out here. This is definitely one of the stops I wanted to come back to, and I hope we can keep this event as long as possible because I really like it.''
The daughter of former tennis players Petr Korda and Regina Raichrtova, the 20-year-old Korda won the 2012 Women's Australian Open for her lone LPGA title.
''Right now it's Friday, so I think really the tournament starts back nine on Sunday,'' Korda said. ''So right now, it's great to have the lead, and I feel good.''
Webb also had a bogey-free round, birdieing the last three holes for a 63.
The 38-year-old Webb won the last of her 38 LPGA titles in 2011. The Australian played alongside Korda and Brittany Lincicome the first two rounds.
''When you're playing with Jess and Brittany, if I hit a really good one, I'm 20 yards behind them,'' Webb said. ''In certain parts of the golf course where they can carry parts that I can't, I'm 40 yards behind them, so I'm the little short one out there trying to keep up with the big girls.''
Korda birdied three of the four par-5 holes.
''I reached every single one today, so that's been really nice,'' Korda said. ''Yeah, we give Webby a hard time. She did outdrive me on the first hole today, and she's like, 'What's going on?' And I'm like, 'Did you work out last night?' ... We were just keeping it kind of light out there and having a good time.''
Chella Choi was two strokes back at 11 under after a 66.
''Today and yesterday my putting was really good,'' Choi said. ''My confidence is better.''
Sydnee Michaels had a course-record 62 to join Pornanong Phatlum and Thidapa Suwannapura at 10 under.
''It feels so good to finally have a good round because I've been struggling the last few weeks and going through some swing changes,'' Michaels said. ''The week off last week I just said, 'You know what, I'm just going to go back to what feels good.' So I hit a lot of balls and just kind of got back to where I was feeling good over the ball again. So, it feels so good to finally have a good round.''
Phatlum shot a 65, and Suwannapura had a 67.
Defending champion Stacy Lewis was 4 under after her second straight 70. She had a double bogey on the par-3 14th after hitting it in the water.
''I made too many mistakes, and you can't do it when people are shooting lights out,'' said the second-ranked Lewis, the winner this year in consecutive events in Singapore and Phoenix.
Michelle Wie missed the cut with rounds of 74 and 75. Lincicome also missed the cut, shooting 75-70.