user18150: Currently there are 35 million unspent transaction outputs. Is there a site somewhere where I can query this data to see, for instance, how many UTXO's exist with a value less than 20,000 satoshis? Or the total unique scriptPubKey values found in a  UTXOs?

user19331: The standard bitcoind core daemon has no methods to query the UTXO set for reasons I don't know: it should be trivial to give access to it even on a pruned node since it needs to have the full UTXO set at any time to validate a new block.
Anyway a pull request seems in progress to add this capability:
https://github.com/bitcoin/bitcoin/pull/8952
There are anyway third party apis to query a single address, for example https://www.blockcypher.com/dev/ or https://chain.so/api

18150: <p>Currently there are 35 million unspent transaction outputs. Is there a site somewhere where I can query this data to see, for instance, how many UTXO's exist with a value less than 20,000 satoshis? Or the total unique <code>scriptPubKey</code> values found in a  UTXOs?</p>
 19331: <p>The standard bitcoind core daemon has no methods to query the UTXO set for reasons I don't know: it should be trivial to give access to it even on a pruned node since it needs to have the full UTXO set at any time to validate a new block.</p>

<p>Anyway a pull request seems in progress to add this capability:
<a href="https://github.com/bitcoin/bitcoin/pull/8952" rel="nofollow noreferrer">https://github.com/bitcoin/bitcoin/pull/8952</a></p>

<p>There are anyway third party apis to query a single address, for example <a href="https://www.blockcypher.com/dev/" rel="nofollow noreferrer">https://www.blockcypher.com/dev/</a> or <a href="https://chain.so/api" rel="nofollow noreferrer">https://chain.so/api</a></p>
