diff --git a/Libraries/LibJS/Runtime/MathObject.cpp b/Libraries/LibJS/Runtime/MathObject.cpp
index fd47c7d0cf..613f6cef8f 100644
--- a/Libraries/LibJS/Runtime/MathObject.cpp
+++ b/Libraries/LibJS/Runtime/MathObject.cpp
@@ -38,8 +38,10 @@ MathObject::MathObject()
     put_native_function("random", random);
     put_native_function("sqrt", sqrt, 1);
     put_native_function("floor", floor, 1);
+    put_native_function("ceil", ceil, 1);
     put_native_function("round", round, 1);
     put_native_function("max", max, 2);
+    put_native_function("trunc", trunc, 1);
 
     put("E", Value(M_E));
     put("LN2", Value(M_LN2));
@@ -98,6 +100,17 @@ Value MathObject::floor(Interpreter& interpreter)
     return Value(::floor(number.as_double()));
 }
 
+Value MathObject::ceil(Interpreter& interpreter)
+{
+    if (!interpreter.argument_count())
+        return js_nan();
+
+    auto number = interpreter.argument(0).to_number();
+    if (number.is_nan())
+        return js_nan();
+    return Value(::ceil(number.as_double()));
+}
+
 Value MathObject::round(Interpreter& interpreter)
 {
     if (!interpreter.argument_count())
@@ -127,4 +140,18 @@ Value MathObject::max(Interpreter& interpreter)
     }
 }
 
+Value MathObject::trunc(Interpreter& interpreter)
+{
+    if (!interpreter.argument_count())
+        return js_nan();
+
+    auto number = interpreter.argument(0).to_number();
+    if (number.is_nan())
+        return js_nan();
+
+    if (number.as_double() < 0)
+        return MathObject::ceil(interpreter);
+    return MathObject::floor(interpreter);
+}
+
 }
diff --git a/Libraries/LibJS/Runtime/MathObject.h b/Libraries/LibJS/Runtime/MathObject.h
index eaf5147966..e62e177c5f 100644
--- a/Libraries/LibJS/Runtime/MathObject.h
+++ b/Libraries/LibJS/Runtime/MathObject.h
@@ -42,8 +42,10 @@ private:
     static Value random(Interpreter&);
     static Value sqrt(Interpreter&);
     static Value floor(Interpreter&);
+    static Value ceil(Interpreter&);
     static Value round(Interpreter&);
     static Value max(Interpreter&);
+    static Value trunc(Interpreter&);
 };
 
 }
diff --git a/Libraries/LibJS/Tests/Math.ceil.js b/Libraries/LibJS/Tests/Math.ceil.js
new file mode 100644
index 0000000000..a8507c5eb6
--- /dev/null
+++ b/Libraries/LibJS/Tests/Math.ceil.js
@@ -0,0 +1,19 @@
+function assert(x) { if (!x) throw 1; }
+
+try {
+    assert(Math.ceil(0.95) === 1);
+    assert(Math.ceil(4) === 4);
+    assert(Math.ceil(7.004) == 8);
+    assert(Math.ceil(-0.95) === -0);
+    assert(Math.ceil(-4)    === -4);
+    assert(Math.ceil(-7.004) === -7);
+
+    assert(isNaN(Math.ceil()));
+    assert(isNaN(Math.ceil(NaN)));
+
+    assert(Math.ceil.length === 1);
+
+    console.log("PASS");
+} catch (e) {
+    console.log("FAIL: " + e);
+}
diff --git a/Libraries/LibJS/Tests/Math.trunc.js b/Libraries/LibJS/Tests/Math.trunc.js
new file mode 100644
index 0000000000..29a9f1ad2a
--- /dev/null
+++ b/Libraries/LibJS/Tests/Math.trunc.js
@@ -0,0 +1,18 @@
+function assert(x) { if (!x) throw 1; }
+
+try {
+    assert(Math.trunc(13.37) === 13);
+    assert(Math.trunc(42.84) === 42);
+    assert(Math.trunc(0.123) ===  0);
+    assert(Math.trunc(-0.123) === -0);
+
+    assert(isNaN(Math.trunc(NaN)));
+    assert(isNaN(Math.trunc('foo')));
+    assert(isNaN(Math.trunc()));
+
+    assert(Math.trunc.length === 1);
+
+    console.log("PASS");
+} catch (e) {
+    console.log("FAIL: " + e);
+}