Zcashd default miner - testnet how long for 1 block?

Guys how long now takes one block on zcashd cpu miner on testnet?

2.5 min -> 150 secondsssssss

On main testnet? Is there any block explorer avaiable?

https://explorer.testnet.z.cash/

The testnet explorer is not for the beta2. Its showing version 1000000 whereas the beta2 is 1000001. You wont see if you have mined a block.

You are correct, @str4d is working on updating the block explorer today.

how can we check hashrate in the Zcashd miner?

Run the benchmark. 10 or 20 runs, your preference, From there you'll have the idea of how your miner performs.

How can I run the bench mark?