The Internet has played a key role in allowing some Iranians to communicate since last week's disputed presidential elections, and many international media outlets have used services like Twitter and emails in their coverage, The Telegraph reports.
"We feel that launching Persian is particularly important now, given ongoing events in Iran," Google's principal scientist, Franz Och said, announcing the addition of Farsi to Google Translate, its free online service.
Like YouTube and Twitter, "Google Translate is one more tool that Persian speakers can use to communicate directly to the world, and vice versa - increasing everyone's access to information," he added.
Facebook engineer Eric Kwan said on its blog: "Since the Iranian election last week, people around the world have increasingly been sharing news and information on Facebook about the results and its aftermath."
"Today we're making the entire site available in a beta version of Persian," he added. Several thousand people posted a "thumbs up" reaction to the news, denoting their approval.
The BBC reported that Google and Facebook had hastened up work on their projects because of huge interest in current events in Iran.