diff --git a/tools/addr.py b/tools/addr.py
index 0ef4b105..326b900a 100755
--- a/tools/addr.py
+++ b/tools/addr.py
@@ -1,18 +1,32 @@
 #!/usr/bin/env python3
 import hashlib
 import sys
+import argparse
 
-from pycoin.coins.bitcoin.networks import BitcoinMainnet
+from pycoin.coins.bitcoin.networks import BitcoinTestnet, BitcoinMainnet
 
 import client
 
 def main():
-    conn = client.Connection(('localhost', 50001))
-    addr, = sys.argv[1:]
-    script = BitcoinMainnet.ui.script_for_address(addr)
-    script_hash = hashlib.sha256(script).digest()[::-1].hex()
-    res = conn.call('blockchain.scripthash.get_balance', script_hash)['result']
-    print('{} has {} satoshis'.format(addr, res))
+    parser = argparse.ArgumentParser()
+    parser.add_argument('--testnet', action='store_true')
+    parser.add_argument('address', nargs='+')
+    args = parser.parse_args()
+
+    if args.testnet:
+        Network = BitcoinTestnet
+        port = 60001
+    else:
+        Network = BitcoinMainnet
+        port = 50001
+
+    conn = client.Connection(('localhost', port))
+    for addr in args.address:
+        script = Network.ui.script_for_address(addr)
+        script_hash = hashlib.sha256(script).digest()[::-1].hex()
+        reply = conn.call('blockchain.scripthash.get_balance', script_hash)
+        result = reply['result']
+        print('{} has {} satoshis'.format(addr, result))
 
 
 if __name__ == '__main__':