diff --git a/.gitignore b/.gitignore
index ab45ecb..560db17 100644
--- a/.gitignore
+++ b/.gitignore
@@ -6,3 +6,4 @@ yarn-error.log*
 .npm
 .idea
 .DS_Store
+dist/
diff --git a/.prettierrc b/.prettierrc
new file mode 100644
index 0000000..b89bab0
--- /dev/null
+++ b/.prettierrc
@@ -0,0 +1,6 @@
+{
+  "semi": false,
+  "tabWidth": 2,
+  "singleQuote": true,
+  "trailingComma": "es5"
+}
\ No newline at end of file
diff --git a/CHANGELOG.md b/CHANGELOG.md
new file mode 100644
index 0000000..d8d5510
--- /dev/null
+++ b/CHANGELOG.md
@@ -0,0 +1,10 @@
+# Changelog
+
+##### 1.1.0
+
+* Fix possible incorrect share code string detection
+* TypeScript support
+
+##### 1.0.0
+
+Initial release
diff --git a/README.md b/README.md
index 21b40dd..a08da01 100644
--- a/README.md
+++ b/README.md
@@ -4,7 +4,9 @@ Node module to decode / encode the CSGO share codes used to share game replays b
 
 # Installation
 
-`npm install csgo-sharecode`
+`npm install csgo-sharecode` or `yarn install csgo-sharecode`
+
+TypeScript definitions provided.
 
 # Usage
 
diff --git a/example.js b/example.js
index a919189..e66500b 100644
--- a/example.js
+++ b/example.js
@@ -1,8 +1,10 @@
 // const ShareCode = require('csgo-sharecode');
 // OR using ES modules
 // import ShareCode from 'csgo-sharecode';
-const ShareCode = require('./index');
-
+// import { encode, decode } from 'csgo-sharecode';
+// When using TS you can import the ShareCode (object representation of a full share code) and TwoComplementInteger64 types
+// import { ShareCode, TwoComplementInteger64 } from 'csgo-sharecode';
+const ShareCode = require('./dist')
 
 // sample example:
 // share code: CSGO-GADqf-jjyJ8-cSP2r-smZRo-TO2xK
@@ -20,13 +22,13 @@ const match = {
     low: 143,
   },
   tvPort: 599906796,
-};
+}
 
-console.log('encoding share code:\n', match);
-const code = ShareCode.encode(match.matchId, match.reservationId, match.tvPort);
-console.log('result:\n', code);
+console.log('encoding share code:\n', match)
+const code = ShareCode.encode(match.matchId, match.reservationId, match.tvPort)
+console.log('result:\n', code)
 
-const shareCode = 'CSGO-GADqf-jjyJ8-cSP2r-smZRo-TO2xK';
-console.log('decoding share code:\n', shareCode);
-const info = ShareCode.decode(shareCode);
-console.log('result:\n', info);
+const shareCode = 'CSGO-GADqf-jjyJ8-cSP2r-smZRo-TO2xK'
+console.log('decoding share code:\n', shareCode)
+const info = ShareCode.decode(shareCode)
+console.log('result:\n', info)
diff --git a/index.js b/index.js
deleted file mode 100644
index 4492007..0000000
--- a/index.js
+++ /dev/null
@@ -1,147 +0,0 @@
-'use strict';
-
-const BigNumber = require('bignumber.js');
-
-const DICTIONARY = 'ABCDEFGHJKLMNOPQRSTUVWXYZabcdefhijkmnopqrstuvwxyz23456789';
-const DICTIONARY_LENGTH = DICTIONARY.length;
-const SHARECODE_PATTERN = /CSGO(-?[\w]{5}){5}/;
-
-/**
- * Convert a byte array into a hexadecimal string
- *
- * @param bytes
- * @returns {string}
- */
-function bytesToHex(bytes) {
-  return Array.from(bytes, (byte) => {
-    return ('0' + (byte & 0xff).toString(16)).slice(-2);
-  }).join('');
-}
-
-/**
- * Convert a hexadecimal string into a byte array
- *
- * @param str
- * @returns {Array}
- */
-function hexToBytes(str) {
-  let array = [];
-  for (var i = 0, j = 0; i < str.length; i += 2, j++) {
-    array[j] = parseInt('0x' + str.substr(i, 2));
-  }
-
-  return array;
-}
-
-/**
- * Convert a 64 bit 2 complement integer into a byte array (big endian byte representation)
- *
- * @param high
- * @param low
- * @returns Array
- */
-function longToBytesBE(high, low) {
-  return [
-    (high >>> 24) & 0xff,
-    (high >>> 16) & 0xff,
-    (high >>> 8) & 0xff,
-    (high & 0xff),
-    (low >>> 24) & 0xff,
-    (low >>> 16) & 0xff,
-    (low >>> 8) & 0xff,
-    (low & 0xff)
-  ];
-}
-
-/**
- * Convert an int into a byte array (low bits only)
- *
- * @param number
- * @returns Array
- */
-function int16ToBytes(number) {
-  return [
-    (number & 0x0000ff00) >> 8,
-    (number & 0x000000ff)
-  ];
-}
-
-/**
- * Convert a byte array into an int32
- *
- * @param bytes
- * @returns {number}
- */
-function bytesToInt32(bytes) {
-  let number = 0;
-  for (let i = 0; i < bytes.length; i++) {
-    number += bytes[i];
-    if (i < bytes.length - 1) {
-      number = number << 8;
-    }
-  }
-
-  return number;
-}
-
-module.exports = {
-  /**
-   * Encode a share code from its object data and return its string representation.
-   * Required fields should come from a CDataGCCStrike15_v2_MatchInfo protobuf message.
-   * https://github.com/SteamRE/SteamKit/blob/master/Resources/Protobufs/csgo/cstrike15_gcmessages.proto#L773
-   * @param matchId {Object|Long} match_id
-   * @param reservationId {Object|Long} reservation_id
-   * @param tvPort number tv_port
-   * @return {string} Share code as string
-   */
-  encode: (matchId, reservationId, tvPort) => {
-    const matchBytes = longToBytesBE(matchId.high, matchId.low).reverse();
-    const reservationBytes = longToBytesBE(reservationId.high, reservationId.low).reverse();
-    const tvBytes = int16ToBytes(tvPort).reverse();
-    const bytes = Array.prototype.concat(matchBytes, reservationBytes, tvBytes);
-    const bytesHex = bytesToHex(bytes);
-    let total = new BigNumber(bytesHex, 16);
-
-    let c = '';
-    let rem = 0;
-    for (let i = 0; i < 25; i++) {
-      rem = total.mod(DICTIONARY_LENGTH);
-      c += DICTIONARY[rem.floor()];
-      total = total.div(DICTIONARY_LENGTH);
-    }
-
-    return `CSGO-${c.substr(0, 5)}-${c.substr(5, 5)}-${c.substr(10, 5)}-${c.substr(15, 5)}-${c.substr(20, 5)}`;
-  },
-  /**
-   * Decode a CSGO share code from its string and return its object data representation.
-   * Share code format excepted: CSGO-xxxxx-xxxxx-xxxxx-xxxxx-xxxxx
-   * @param shareCode Share code as string
-   * @return {{matchId: {low: number, high: number}, reservationId: {low: number, high: number}, tvPort: number}}
-   */
-  decode: (shareCode) => {
-    if (!shareCode.match(SHARECODE_PATTERN)) {
-      throw new Error('Invalid share code');
-    }
-
-    shareCode = shareCode.replace(/CSGO|-/g, '');
-    shareCode = Array.from(shareCode).reverse();
-    let big = new BigNumber(0);
-    for (let i = 0; i < shareCode.length; i++) {
-      big = big.mul(DICTIONARY_LENGTH).add(DICTIONARY.indexOf(shareCode[i]));
-    }
-
-    const bytes = hexToBytes(big.toString(16));
-
-    return {
-      matchId: {
-        low: bytesToInt32(bytes.slice(0, 4).reverse()),
-        high: bytesToInt32(bytes.slice(4, 8).reverse()),
-      },
-      reservationId: {
-        low: bytesToInt32(bytes.slice(8, 12).reverse()),
-        high: bytesToInt32(bytes.slice(12, 16).reverse()),
-      },
-      tvPort: bytesToInt32(bytes.slice(16, 18).reverse()),
-    };
-  }
-};
diff --git a/index.ts b/index.ts
new file mode 100644
index 0000000..cfc20c3
--- /dev/null
+++ b/index.ts
@@ -0,0 +1,143 @@
+import BigNumber from 'bignumber.js'
+
+const DICTIONARY = 'ABCDEFGHJKLMNOPQRSTUVWXYZabcdefhijkmnopqrstuvwxyz23456789'
+const DICTIONARY_LENGTH = DICTIONARY.length
+const SHARECODE_PATTERN = /CSGO(-?[\w]{5}){5}$/
+
+export interface TwoComplementInteger64 {
+  low: number
+  high: number
+  unsigned?: boolean
+}
+
+export interface Sharecode {
+  matchId: TwoComplementInteger64
+  reservationId: TwoComplementInteger64
+  tvPort: number
+}
+
+/**
+ * Convert a byte array into a hexadecimal string
+ */
+function bytesToHex(bytes: number[]) {
+  return Array.from(bytes, byte => {
+    return ('0' + (byte & 0xff).toString(16)).slice(-2)
+  }).join('')
+}
+
+/**
+ * Convert a hexadecimal string into a byte array
+ */
+function hexToBytes(str: string) {
+  let array = []
+  for (var i = 0, j = 0; i < str.length; i += 2, j++) {
+    array[j] = parseInt('0x' + str.substr(i, 2))
+  }
+
+  return array
+}
+
+/**
+ * Convert a 64 bit 2 complement integer into a byte array (big endian byte representation)
+ */
+function longToBytesBE(high: number, low: number) {
+  return [
+    (high >>> 24) & 0xff,
+    (high >>> 16) & 0xff,
+    (high >>> 8) & 0xff,
+    high & 0xff,
+    (low >>> 24) & 0xff,
+    (low >>> 16) & 0xff,
+    (low >>> 8) & 0xff,
+    low & 0xff,
+  ]
+}
+
+/**
+ * Convert an int into a byte array (low bits only)
+ */
+function int16ToBytes(number: number) {
+  return [(number & 0x0000ff00) >> 8, number & 0x000000ff]
+}
+
+/**
+ * Convert a byte array into an int32
+ */
+function bytesToInt32(bytes: number[]) {
+  let number = 0
+  for (let i = 0; i < bytes.length; i++) {
+    number += bytes[i]
+    if (i < bytes.length - 1) {
+      number = number << 8
+    }
+  }
+
+  return number
+}
+
+/**
+ * Encode a share code from its ShareCode object type and return its string representation.
+ * Required fields should come from a CDataGCCStrike15_v2_MatchInfo protobuf message.
+ * https://github.com/SteamRE/SteamKit/blob/master/Resources/Protobufs/csgo/cstrike15_gcmessages.proto#L785
+ */
+const encode = (
+  matchId: TwoComplementInteger64,
+  reservationId: TwoComplementInteger64,
+  tvPort: number
+): string => {
+  const matchBytes = longToBytesBE(matchId.high, matchId.low).reverse()
+  const reservationBytes = longToBytesBE(
+    reservationId.high,
+    reservationId.low
+  ).reverse()
+  const tvBytes = int16ToBytes(tvPort).reverse()
+  const bytes = Array.prototype.concat(matchBytes, reservationBytes, tvBytes)
+  const bytesHex = bytesToHex(bytes)
+  let total = new BigNumber(bytesHex, 16)
+
+  let c = ''
+  let rem: BigNumber = new BigNumber(0)
+  for (let i = 0; i < 25; i++) {
+    rem = total.mod(DICTIONARY_LENGTH)
+    c += DICTIONARY[rem.integerValue(BigNumber.ROUND_FLOOR).toNumber()]
+    total = total.div(DICTIONARY_LENGTH)
+  }
+
+  return `CSGO-${c.substr(0, 5)}-${c.substr(5, 5)}-${c.substr(
+    10,
+    5
+  )}-${c.substr(15, 5)}-${c.substr(20, 5)}`
+}
+
+/**
+ * Decode a CSGO share code from its string and return it as a ShareCode object type.
+ * Share code format excepted: CSGO-xxxxx-xxxxx-xxxxx-xxxxx-xxxxx
+ */
+const decode = (shareCode: string): Sharecode => {
+  if (!shareCode.match(SHARECODE_PATTERN)) {
+    throw new Error('Invalid share code')
+  }
+
+  shareCode = shareCode.replace(/CSGO|-/g, '')
+  const chars = Array.from(shareCode).reverse()
+  let big = new BigNumber(0)
+  for (let i = 0; i < chars.length; i++) {
+    big = big.multipliedBy(DICTIONARY_LENGTH).plus(DICTIONARY.indexOf(chars[i]))
+  }
+
+  const bytes = hexToBytes(big.toString(16))
+
+  return {
+    matchId: {
+      low: bytesToInt32(bytes.slice(0, 4).reverse()),
+      high: bytesToInt32(bytes.slice(4, 8).reverse()),
+    },
+    reservationId: {
+      low: bytesToInt32(bytes.slice(8, 12).reverse()),
+      high: bytesToInt32(bytes.slice(12, 16).reverse()),
+    },
+    tvPort: bytesToInt32(bytes.slice(16, 18).reverse()),
+  }
+}
+
+export { encode, decode }
diff --git a/package-lock.json b/package-lock.json
new file mode 100644
index 0000000..27fdac6
--- /dev/null
+++ b/package-lock.json
@@ -0,0 +1,25 @@
+{
+  "name": "csgo-sharecode",
+  "version": "1.1.0",
+  "lockfileVersion": 1,
+  "requires": true,
+  "dependencies": {
+    "bignumber.js": {
+      "version": "7.2.1",
+      "resolved": "https://registry.npmjs.org/bignumber.js/-/bignumber.js-7.2.1.tgz",
+      "integrity": "sha512-S4XzBk5sMB+Rcb/LNcpzXr57VRTxgAvaAEDAl1AwRx27j00hT84O6OkteE7u8UB3NuaaygCRrEpqox4uDOrbdQ=="
+    },
+    "prettier": {
+      "version": "1.14.2",
+      "resolved": "https://registry.npmjs.org/prettier/-/prettier-1.14.2.tgz",
+      "integrity": "sha512-McHPg0n1pIke+A/4VcaS2en+pTNjy4xF+Uuq86u/5dyDO59/TtFZtQ708QIRkEZ3qwKz3GVkVa6mpxK/CpB8Rg==",
+      "dev": true
+    },
+    "typescript": {
+      "version": "3.0.1",
+      "resolved": "https://registry.npmjs.org/typescript/-/typescript-3.0.1.tgz",
+      "integrity": "sha512-zQIMOmC+372pC/CCVLqnQ0zSBiY7HHodU7mpQdjiZddek4GMj31I3dUJ7gAs9o65X7mnRma6OokOkc6f9jjfBg==",
+      "dev": true
+    }
+  }
+}
diff --git a/package.json b/package.json
index ea9f692..f64940c 100644
--- a/package.json
+++ b/package.json
@@ -1,8 +1,8 @@
 {
   "name": "csgo-sharecode",
-  "version": "1.0.1",
+  "version": "1.1.0",
   "description": "Encode / decode CSGO share code",
-  "main": "index.js",
+  "main": "dist/index.js",
   "author": {
     "name": "AkiVer",
     "email": "ys.renaud@gmail.com"
@@ -12,7 +12,7 @@
     "type": "git",
     "url": "https://github.com/akiver/csgo-sharecode.git"
   },
-  "homepage": "http://github.com/akiver/csgo-sharecode",
+  "homepage": "https://github.com/akiver/csgo-sharecode",
   "keywords": [
     "csgo",
     "valve",
@@ -20,10 +20,23 @@
     "replays",
     "demos"
   ],
+  "files": [
+    "dist",
+    "index.ts",
+    "index.d.ts"
+  ],
+  "scripts": {
+    "build": "npx tsc",
+    "dev": "npx tsc --watch"
+  },
   "dependencies": {
-    "bignumber.js": "^4.0.4"
+    "bignumber.js": "^7.2.1"
   },
   "engines": {
     "node": ">=4.0.0"
+  },
+  "devDependencies": {
+    "prettier": "^1.14.2",
+    "typescript": "^3.0.1"
   }
 }
diff --git a/tsconfig.json b/tsconfig.json
new file mode 100644
index 0000000..88e8ccd
--- /dev/null
+++ b/tsconfig.json
@@ -0,0 +1,15 @@
+{
+    "compilerOptions": {
+        "declaration": true,
+        "lib": ["es5", "es6"],
+        "noImplicitAny": true,
+        "noUnusedLocals": true,
+        "outDir": "./dist",
+        "sourceMap": true,
+        "strictNullChecks": true,
+        "target": "es5",
+    },
+    "files": [
+        "index.ts",
+    ]
+}
\ No newline at end of file