Jack Dorsey pledged $US1 billion ($1.6 billion) of his stake in Square Inc., the payments firm he co-founded and heads, to coronavirus relief efforts - the largest pandemic-related donation yet.

"After we disarm this pandemic, the focus will shift to girl's health and education, and UBI," Dorsey said Tuesday in a tweet, referring to universal basic income. The donation represents about 28 per cent of his wealth, he said.

"I hope this inspires others to do something similar," Dorsey said Tuesday in a tweet. "Life is too short, so let's do everything we can today to help people now."

Jack Dorsey's pledge is so far the biggest by America's billionaires announced so far. Credit:Bloomberg

Dorsey has been working from his home in San Francisco's affluent Sea Cliff neighbourhood, following shelter-in-place orders that are keeping many people from their regular activities. Also the co-founder and chief executive officer of Twitter, he has a net worth of about $US3.9 billion, according to the Bloomberg Billionaires Index.