Base64 Javascript

function textToBinary(str='', sep=' ') {
    let result = '';
    result = str.split('').map(char => {
        let bite = char.charCodeAt(0).toString(2);
        while (bite.length < 8) {
            bite = '0'+bite;
        }
        return bite
    }).join(sep);

    return result;
}

function groupSplit(str, n=1) {
    return str.match(new RegExp('.{1,'+n+'}', 'g'));
}

function toBase64(str, addEq=true) {
    const base64charset = [
        'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H',
        'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P',
        'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X',
        'Y', 'Z', 'a', 'b', 'c', 'd', 'e', 'f',
        'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n',
        'o', 'p', 'q', 'r', 's', 't', 'u', 'v',
        'w', 'x', 'y', 'z', '0', '1', '2', '3',
        '4', '5', '6', '7', '8', '9', '+', '/'
    ]

    let binary = textToBinary(str, '');
    let chunks = groupSplit(binary, 6);
    let vals = [];
    let result = '';
    let eq = 0;

    chunks.forEach(function(val, index) {
        while (val.length < 6) {
            val += '0';
            eq++;
        }
        vals.push((parseInt(val, 2)));
    });

    vals.forEach(function(val, index) {
        result += base64charset[val];
    });

    if (addEq) {
        for (let i = 0; i < eq/2; i++) {
            result += '=';
        }
    }
    return result;
}

console.log(toBase64("Hello, World!")); // SGVsbG8sIFdvcmxkIQ==