The British women reached the third round in Melbourne, and both are up 10 places in the latest published list.
Watson is now ranked No 40 - three places ahead of her compatriot, whose two beaten opponents in Australia included former Wimbledon champion Petra Kvitova.
Robson was eventually beaten by fellow teenager Sloane Stephens, who is up to No 17 after reaching the semi-finals.
Victoria Azarenka, who came from behind to defeat Li Na i the final, retains her No 1 status ahead of new No 2 Serena Williams.
The top three in the men's rankings remain unchanged, but David Ferrer moved above the injured Rafa Nadal into fourth place thanks to his semi-final appearance.