The Australian Open champion fired 47 winners to Errani's 23 and broke the Italian six times to set up a meeting with France's Pauline Parmentier.
Also advancing to the quarter-finals was Maria Sakkari who eased past Aleksandra Krunic 6-3 6-1. She was joined by Arantxa Rus of the Netherlands who came through a tough three-setter against Danka Kovinic.
Slovenia's Polona Hercog progressed to the last eight after her opponent Kateryna Bondarenko pulled out of their match due to injury. Hercog was ahead 6-2 1-1 when Ukraine's Bondarenko retired.
Donna Vekic overcame Australia's Ajla Tomljanovic 6-1 6-2 and takes on Irina-Camelia Begu in the quarter-finals.
(Reporting by Shrivathsa Sridhar in Bengaluru, editing by Ed Osmond)
