cat count

count provides quick access to the document count of the entire cluster, or individual indices.

% curl 192.168.56.10:9200/_cat/indices
green wiki1 3 0 10000 331 168.5mb 168.5mb
green wiki2 3 0   428   0     8mb     8mb

% curl 192.168.56.10:9200/_cat/count
1384314124582 19:42:04 10428

% curl 192.168.56.10:9200/_cat/count/wiki2
1384314139815 19:42:19 428

The document count indicates the number of live documents and does not include deleted documents which have not yet been cleaned up by the merge process.