What is Block Time and Why does it Matter? - Tokenview Block Explorer
Block time is the time required to create the next block in a chain. The shorter block time means that the chance of a temporary fork will be greatly improved. When a miner digs a new block, it needs to be broadcast to the entire network. The broadcast process takes time. If the block generation time is short, other nodes may not have received the block released by the miner, and they have already dug a block of the same height, Which caused a temporary fork.
Tokenview block explorer enables you to search average block time for example the eth block time and just click the websites: https://eth.tokenview.com/en/chart/blockTime