The read and write speeds of USB flash drives can vary widely depending on several factors, including the quality of the flash memory and controller, the interface type (USB 2.0, USB 3.0, USB-C, etc.), and the size and type of files being transferred.

For USB 2.0 drives, the maximum theoretical transfer speed is 480 Mbps (megabits per second) for both read and write operations. For USB 3.0 drives, the maximum theoretical transfer speed is 5 Gbps (gigabits per second) for both read and write operations. However, actual transfer speeds may be lower than these maximum values, and can be affected by factors such as the size and type of files being transferred and the quality of the USB controller and flash memory.

In general, modern USB flash drives can achieve read speeds of around 100-200 MB/s (megabytes per second) and write speeds of around 20-100 MB/s, depending on the factors mentioned above. However, there can be significant variation between different models and brands of USB flash drives. It’s important to check the specifications and reviews of a particular USB flash drive to get a more accurate idea of its performance.