LOS ANGELES (AFP) - Amazon founder Jeff Bezos was a US$100 billion (S$135 billion) man on Monday as the online retail colossus raked in cash from the holiday weekend's cyber shopping spree.

Forbes magazine's real-time ranking of the richest people had Mr Bezos on top, with a personal net worth of US$100.3 billion.

Microsoft co-founder Bill Gates saw his net worth climb to US$89.4 billion but was relegated to being the second most affluent person on the planet.

Mr Bezos owns almost 17 per cent of Amazon, which he founded in a Seattle garage in 1994 after quitting a hedge fund job to sell books online.

Amazon shares finished the official trading day up just shy of a per cent, and inched up a bit more in after-market trades to top US$1,200.

Based on the share price, Seattle-based Amazon had a market value of some US$576.3 billion.

Market tracker Adobe Digital Insights data showed that online shopping was at a record-setting pace from Black Friday to Cyber Monday.