calculateCrashPoint.js

....
exports.genGameHash = function(serverSeed) {
    return crypto.createHash('sha256').update(serverSeed).digest('hex');
};

function divisible(hash, mod) {
    // We will read in 4 hex at a time, but the first chunk might be a bit smaller
    // So ABCDEFGHIJ should be chunked like  AB CDEF GHIJ
    var val = 0;

    var o = hash.length % 4;
    for (var i = o > 0 ? o - 4 : 0; i < hash.length; i += 4) {
        val = ((val << 16) + parseInt(hash.substring(i, i+4), 16)) % mod;
    }

    return val === 0;
}


// newest for zcash block 135400  
var clientSeed ='0000000003a96dc6e52672a487ec577fc32e71a8f99bdbbf7329bf27f9772544';

exports.crashPointFromHash = function(serverSeed) {
    var hash = crypto.createHmac('sha256', serverSeed).update(clientSeed).digest('hex');

    // In 1 of 101 games the game crashes instantly.
    if (divisible(hash, 101))
        return 0;

    // Use the most significant 52-bit from the hash to calculate the crash point
    var h = parseInt(hash.slice(0,52/4),16);
    var e = Math.pow(2,52);

    return Math.floor((100 * e - h) / (e - h));
};