user77017: I was wondering how  testnet addresses like https://testnet.blockchain.info/address/myaj43o2wt34j31ej5pmP6htCHFafAKoeP
are created? 
Also is there a script to create them?

user38482: this address is a standard P2PKH testnet address, and can be derived from a typical priv/public keypair, by adding the testnet prefix. There is a page you can play with - in Step 4 you would change the default prefix "00" to "6F", and get a corresponding address. The composition of such an address and further details are again in the wiki . 

77017: <p>I was wondering how  testnet addresses like <a href="https://testnet.blockchain.info/address/myaj43o2wt34j31ej5pmP6htCHFafAKoeP" rel="nofollow noreferrer">https://testnet.blockchain.info/address/myaj43o2wt34j31ej5pmP6htCHFafAKoeP</a>
are created? 
Also is there a script to create them?</p>
 38482: <p>this address is a standard P2PKH testnet address, and can be derived from a typical priv/public keypair, by adding <a href="https://en.bitcoin.it/wiki/List_of_address_prefixes" rel="nofollow noreferrer">the testnet prefix</a>. There is a page you can <a href="http://gobittest.appspot.com/Address" rel="nofollow noreferrer">play with</a> - in Step 4 you would change the default prefix "00" to "6F", and get a corresponding address. The composition of such an address and further details are again in <a href="https://en.bitcoin.it/wiki/Technical_background_of_version_1_Bitcoin_addresses" rel="nofollow noreferrer">the wiki</a> . </p>
