About 25 billion transistors.
Recently, TSMC officially disclosed the latest 3-nanometer process technology details, transistor density up to 250 million\/mm2. According to the standard of 5-nanometer and 4-nanometer chips, the chip area is basically 100 square millimeters, so the original on TSMC's 3-nanometer chip should be about 25 billion. However, there are some technical differences between TSMC and Samsung, which are currently able to manufacture 3-nanometer chips, and Samsung is slightly weaker, so Samsung 3-nanometer chips should not reach 25 billion.