diff --git a/package.json b/package.json
index b2bae50..67d8c43 100644
--- a/package.json
+++ b/package.json
@@ -9,7 +9,7 @@
   },
   "scripts": {
     "prepublish": "gulp",
-    "test": "mocha --require source-map-support/register --reporter spec"
+    "test": "mocha --recursive --require source-map-support/register --reporter spec"
   },
   "keywords": [
     "minecraft",
@@ -29,6 +29,7 @@
   "browser": "browser.js",
   "devDependencies": {
     "batch": "~0.3.1",
+    "chai": "^2.3.0",
     "gulp": "^3.8.11",
     "gulp-babel": "^5.1.0",
     "gulp-plumber": "^1.0.1",
diff --git a/test/dataTypes/numeric.js b/test/dataTypes/numeric.js
new file mode 100644
index 0000000..049bdd5
--- /dev/null
+++ b/test/dataTypes/numeric.js
@@ -0,0 +1,248 @@
+var expect = require('chai').expect;
+
+var numeric = require('../../dist/datatypes/numeric');
+var getReader = function(dataType) { return dataType[0]; };
+var getWriter = function(dataType) { return dataType[1]; };
+var getSizeOf = function(dataType) { return dataType[2]; };
+/*var getReader = require('../../lib/utils').getReader;
+var getWriter = require('../../lib/utils').getWriter;
+var getSizeOf = require('../../lib/utils').getSizeOf;*/
+
+var testData = {
+  'byte': {
+    'readPos': {
+      'buffer': new Buffer([0x3d]),
+      'value': 61
+    },
+    'readNeg': {
+      'buffer': new Buffer([0x86]),
+      'value': -122
+    },
+    'writePos': {
+      'buffer': new Buffer([0x00]),
+      'value': 32,
+      'bufferAfter': new Buffer([0x20])
+    },
+    'writeNeg': {
+      'buffer': new Buffer([0x00]),
+      'value': -122,
+      'bufferAfter': new Buffer([0x86])
+    },
+    'sizeof': {
+      'value': 0x2d,
+      'size': 1,
+    }
+  },
+  'ubyte': {
+    'readPos': {
+      'buffer': new Buffer([0x3d]),
+      'value': 61
+    },
+    'readNeg': {
+      'buffer': new Buffer([0x86]),
+      'value': 134
+    },
+    'writePos': {
+      'buffer': new Buffer([0x00]),
+      'value': 61,
+      'bufferAfter': new Buffer([0x3d])
+    },
+    'writeNeg': {
+      'buffer': new Buffer([0x00]),
+      'value': 134,
+      'bufferAfter': new Buffer([0x86])
+    },
+    'sizeof': {
+      'value': 0x2d,
+      'size': 1,
+    }
+  },
+  'short': {
+    'readPos': {
+      'buffer': new Buffer([0x30, 0x87]),
+      'value': 12423
+    },
+    'readNeg': {
+      'buffer': new Buffer([0xef, 0x77]),
+      'value': -4233
+    },
+    'writePos': {
+      'buffer': new Buffer([0x00, 0x00]),
+      'value': 12423,
+      'bufferAfter': new Buffer([0x30, 0x87]),
+    },
+    'writeNeg': {
+      'buffer': new Buffer([0x00, 0x00]),
+      'value': -4233,
+      'bufferAfter': new Buffer([0xef, 0x77])
+    },
+    'sizeof': {
+      'value': 0x2d,
+      'size': 2,
+    }
+  },
+  'ushort': {
+    'readPos': {
+      'buffer': new Buffer([0x30, 0x87]),
+      'value': 12423
+    },
+    'readNeg': {
+      'buffer': new Buffer([0xef, 0x77]),
+      'value': 61303
+    },
+    'writePos': {
+      'buffer': new Buffer([0x00, 0x00]),
+      'value': 12423,
+      'bufferAfter': new Buffer([0x30, 0x87]),
+    },
+    'writeNeg': {
+      'buffer': new Buffer([0x00, 0x00]),
+      'value': 61303,
+      'bufferAfter': new Buffer([0xef, 0x77])
+    },
+    'sizeof': {
+      'value': 0x2d,
+      'size': 2,
+    }
+  },
+  'int': {
+    'readPos': {
+      'buffer': new Buffer([0x00, 0x00, 0x00, 0xea]),
+      'value': 234
+    },
+    'readNeg': {
+      'buffer': new Buffer([0xff, 0xff, 0xfc, 0x00]),
+      'value': -1024
+    },
+    'writePos': {
+      'buffer': new Buffer([0x00, 0x00, 0x00, 0x00]),
+      'value': 234,
+      'bufferAfter': new Buffer([0x00, 0x00, 0x00, 0xea])
+    },
+    'writeNeg': {
+      'buffer': new Buffer([0x00, 0x00, 0x00, 0x00]),
+      'value': -1024,
+      'bufferAfter': new Buffer([0xff, 0xff, 0xfc, 0x00])
+    },
+    'sizeof': {
+      'value': 0x2d,
+      'size': 4
+    }
+  },
+  'uint': {
+    'readPos': {
+      'buffer': new Buffer([0x00, 0x00, 0x00, 0xea]),
+      'value': 234
+    },
+    'readNeg': {
+      'buffer': new Buffer([0xff, 0xff, 0xfc, 0x00]),
+      'value': 4294966272
+    },
+    'writePos': {
+      'buffer': new Buffer([0x00, 0x00, 0x00, 0x00]),
+      'value': 234,
+      'bufferAfter': new Buffer([0x00, 0x00, 0x00, 0xea])
+    },
+    'writeNeg': {
+      'buffer': new Buffer([0x00, 0x00, 0x00, 0x00]),
+      'value': 4294966272,
+      'bufferAfter': new Buffer([0xff, 0xff, 0xfc, 0x00])
+    },
+    'sizeof': {
+      'value': 0x2d,
+      'size': 4
+    }
+  },
+  'float': {
+    'readPos': {
+      'buffer': new Buffer([0x47, 0x05, 0xc3, 0x00]),
+      'value': 34243
+    },
+    'readNeg': {
+      'buffer': new Buffer([0xc6, 0x42, 0x4c, 0x00]),
+      'value': -12435
+    },
+    'writePos': {
+      'buffer': new Buffer([0x00, 0x00, 0x00, 0x00]),
+      'value': 34243,
+      'bufferAfter': new Buffer([0x47, 0x05, 0xc3, 0x00])
+    },
+    'writeNeg': {
+      'buffer': new Buffer([0x00, 0x00, 0x00, 0x00]),
+      'value': -12435,
+      'bufferAfter': new Buffer([0xc6, 0x42, 0x4c, 0x00])
+    },
+    'sizeof': {
+      'value': 0x2d,
+      'size': 4
+    }
+  },
+  'double': {
+    'readPos': {
+      'buffer': new Buffer([0x40, 0xe0, 0xb8, 0x60, 0x00, 0x00, 0x00, 0x00]),
+      'value': 34243
+    },
+    'readNeg': {
+      'buffer': new Buffer([0xc0, 0xc8, 0x49, 0x80, 0x00, 0x00, 0x00, 0x00]),
+      'value': -12435
+    },
+    'writePos': {
+      'buffer': new Buffer([0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00]),
+      'value': 34243,
+      'bufferAfter': new Buffer([0x40, 0xe0, 0xb8, 0x60, 0x00, 0x00, 0x00, 0x00]),
+    },
+    'writeNeg': {
+      'buffer': new Buffer([0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00]),
+      'value': -12435,
+      'bufferAfter': new Buffer([0xc0, 0xc8, 0x49, 0x80, 0x00, 0x00, 0x00, 0x00]),
+    },
+    'sizeof': {
+      'value': 0x2d,
+      'size': 8
+    }
+  }
+};
+
+describe('Numeric', function() {
+  for (var key in testData) {
+    if (testData.hasOwnProperty(key) && numeric.hasOwnProperty(key)) {
+      var value = testData[key];
+      describe('.' + key, function() {
+        var reader;
+        var writer;
+        var sizeof;
+        before(function() {
+          reader = getReader(numeric[key]);
+          writer = getWriter(numeric[key]);
+          sizeof = getSizeOf(numeric[key]);
+        });
+        it('Returns null if not enough data is provided', function() {
+          expect(reader(new Buffer(0), 0)).to.eql(null);
+        });
+        it('Reads positive values', function() {
+          expect(reader(value.readPos.buffer, 0).value).to.deep.eql(value.readPos.value);
+        });
+        it('Reads big/negative values', function() {
+          expect(reader(value.readNeg.buffer, 0).value).to.deep.eql(value.readNeg.value);
+        });
+        it('Writes positive values', function() {
+          writer(value.writePos.value, value.writePos.buffer, 0);
+          expect(value.writePos.buffer).to.deep.eql(value.writePos.bufferAfter);
+        });
+        it('Writes negative values', function() {
+          writer(value.writeNeg.value, value.writeNeg.buffer, 0);
+          expect(value.writeNeg.buffer).to.deep.eql(value.writeNeg.bufferAfter);
+        });
+        it('Calculates size', function() {
+          var size;
+          if (typeof sizeof === "function") {
+            size = sizeof(value.sizeof.value);
+          } else {
+            size = sizeof;
+          }
+          expect(size).to.eql(value.sizeof.size);
+        });
+      });
+    }
+  }
+});