Apple, Microsoft, and Nvidia are the biggest companies measured by market cap. Apple is the largest company in the world, with a market cap of $3.41 trillion. It's followed by Microsoft ($3.11 trillion), Nvidia ($2.88 trillion), Alphabet ($2.13 trillion), and Amazon ($1.95 trillion).

* Market cap information from Yahoo Finance, as of Sept. 28, 2023. This list includes the biggest companies by their market capitalization or market cap, that is, the total value of all their outstanding shares of stock, rather than other measures such as sales.

He has held positions in, and has deep experience with, expense auditing, personal finance, real estate, as well as fact checking & editing. The world's biggest companies by market capitalization are mainly tech companies, although other sectors, such as energy, financial services, and pharmaceutical, also make an appearance in the top 10.

The largest tech company by market cap is Apple (AAPL) with a market cap of $2.753 T and a current price of $175.05.