Overview of blockchains by cryptocurrency:

Bitcoin-https://blockchain.info/
	https://blockexplorer.com/

Ethereum-https://etherscan.io/
	https://www.etherchain.org/

Zcash-https://zcash.blockexplorer.com/

Monero-(not very helpful by design) https://monerohash.com/explorer/

Dogecoin-https://dogechain.info/chain/Dogecoin