Consumers are increasingly using their Web e-mail inboxes as a repository for e-mail as well as digital photos and documents. Web e-mail providers have been responding with offers of ever more free storage.
Yahoo said the global storage upgrade will begin in late April and take about two weeks to complete.
The Internet media company also said it is beefing up antivirus protection for free e-mail users, giving them the ability to remove viruses from attachments -- a feature that had only been available to paying users.
Yahoo Mail is available in 15 languages in almost two dozen countries around the world.
rediff.com has been offering 1 gigabyte of storage in its free e-mail service Rediffmail for a long time now.