There is no web based block explorer yet, but there will be one available before the regular release! If you take a look at the OPAL wallet you can also get a vague idea of how the built in block explorer (in the ATOMIC client) will work

Unfortunately we can't make much use of any of the existing open-source blockchain explorers except as a reference since they aren't able to get the information from transaction scripts that is actually pertinent to our blockchain.

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Also glad to see that BTER is back to life, this onslaught of centralized exchange issues will certainly pave the way (or give people a reason to pay attention to) decentralized exchanges.