Apple’s stock has fallen along with a sell-off in the broader market.

The stock of the world’s most valuable company has now fallen more than 20 per cent from its all-time high of $705.07, hit on September 21. That was the day the latest iPhone went on sale.

The sell-off comes as Apple readies other new products for sale, including the iPad Mini.

The Cupertino, California company warned late last month the costs of making new gadgets would cut into profit in its holiday quarter.

Apple Inc. still has the world’s heftiest market capitalisation at $US548 billion ($A528.37 billion). Oil giant Exxon Mobil Corp is next, at nearly $US418 billion.

Apple shares fell 3.8 per cent to close at $558 Wednesday. The tech-heavy Nasdaq composite index fell 2.5 per cent.