Up to what speed can Category 5 UTP cable transmit data?

10 Mb/s describes the maximum throughput of Category 3 UTP cable used for legacy 10BASE-T Ethernet, which is far below Cat 5 capability.

100 Mb/s is the speed supported by 100BASE-TX over Cat 5, but it is not the maximum - Cat 5 can also carry 1000BASE-T at 1000 Mb/s.

The IEEE 802.3ab standard (1000BASE-T) was explicitly defined to operate over four-pair Category 5 UTP cable by using all four pairs simultaneously with advanced encoding, making 1000 Mb/s the maximum rated speed for Cat 5. While Cat 5e later became the preferred minimum due to improved crosstalk specs, Cat 5 itself is capable of carrying Gigabit Ethernet and 1000 Mb/s represents its ceiling, not just 100 Mb/s.

10000 Mb/s (10 Gbps) requires Category 6A or higher cable because 10GBASE-T demands 500 MHz bandwidth and far stricter alien crosstalk margins than Cat 5 provides.