Base32 Crockford's edition https://github.com/agnoster/base32-js 0123456789abcdefghjkmnpqrtuvwxyz

base32crock.js

(function () {
    var alphabet = '0123456789abcdefghjkmnpqrtuvwxyz';
    var alias = {
            o: 0,
            i: 1,
            l: 1,
            s: 5
        };
    var lookup = function () {
        var table = {};
        for (var i = 0; i < alphabet.length; i++) {
            table[alphabet[i]] = i;
        }
        for (var key in alias) {
            if (!alias.hasOwnProperty(key))
                continue;
            table[key] = table['' + alias[key]];
        }
        lookup = function () {
            return table;
        };
        return table;
    };
    function Encoder() {
        var skip = 0;
        var bits = 0;
        this.output = '';
        this.readByte = function (byte) {
            if (typeof byte == 'string')
                byte = byte.charCodeAt(0);
            if (skip < 0) {
                bits |= byte >> -skip;
            } else {
                bits = byte << skip & 248;
            }
            if (skip > 3) {
                skip -= 8;
                return 1;
            }
            if (skip < 4) {
                this.output += alphabet[bits >> 3];
                skip += 5;
            }
            return 0;
        };
        this.finish = function (check) {
            var output = this.output + (skip < 0 ? alphabet[bits >> 3] : '') + (check ? '$' : '');
            this.output = '';
            return output;
        };
    }
    Encoder.prototype.update = function (input, flush) {
        for (var i = 0; i < input.length;) {
            i += this.readByte(input[i]);
        }
        var output = this.output;
        this.output = '';
        if (flush) {
            output += this.finish();
        }
        return output;
    };
    function Decoder() {
        var skip = 0;
        var byte = 0;
        this.output = '';
        this.readChar = function (char) {
            if (typeof char != 'string') {
                if (typeof char == 'number') {
                    char = String.fromCharCode(char);
                }
            }
            char = char.toLowerCase();
            var val = lookup()[char];
            if (typeof val == 'undefined') {
                return;
            }
            val <<= 3;
            byte |= val >>> skip;
            skip += 5;
            if (skip >= 8) {
                this.output += String.fromCharCode(byte);
                skip -= 8;
                if (skip > 0)
                    byte = val << 5 - skip & 255;
                else
                    byte = 0;
            }
        };
        this.finish = function (check) {
            var output = this.output + (skip < 0 ? alphabet[bits >> 3] : '') + (check ? '$' : '');
            this.output = '';
            return output;
        };
    }
    Decoder.prototype.update = function (input, flush) {
        for (var i = 0; i < input.length; i++) {
            this.readChar(input[i]);
        }
        var output = this.output;
        this.output = '';
        if (flush) {
            output += this.finish();
        }
        return output;
    };
    function encode(input) {
        var encoder = new Encoder();
        var output = encoder.update(input, true);
        return output;
    }
    function decode(input) {
        var decoder = new Decoder();
        var output = decoder.update(input, true);
        return output;
    }
    var base32 = {
            Decoder: Decoder,
            Encoder: Encoder,
            encode: encode,
            decode: decode,
        };
    if (typeof window !== 'undefined') {
        window.base32 = base32;
    }
    if (typeof module !== 'undefined' && module.exports) {
        module.exports = base32;
    }
}());