GET Bestblockhash Endpoint GET /api/[$coin]/bestblockhash/ //Returns the hash of the best (tip) block in the most-work fully-validated chain [OPTIONS] $coin (string): btc or ltc or doge or grlc
curl "https://opreturn.net/api/btc/bestblockhash/"
{
"coin": "btc",
"cmd": "bestblockhash",
"success": true,
"bestblockhash": "0000000000000000000256864e7d17665e891d6a3619f97221ffad764d020157"
}