diff --git a/src/sources/rgba.js b/src/sources/rgba.js
index 3ba3670..b8d8552 100644
--- a/src/sources/rgba.js
+++ b/src/sources/rgba.js
@@ -54,7 +54,7 @@ function toHex(rgba) {
     ];
 
     if (rgba.a < 1) {
-        hexList.push(round(rgba.a));
+        hexList.push(toString16(round(rgba.a * 255)));
     }
 
     return '#' + hexList.join('');
diff --git a/test/sources/test.rgba.js b/test/sources/test.rgba.js
index fc65fbb..fce6c26 100644
--- a/test/sources/test.rgba.js
+++ b/test/sources/test.rgba.js
@@ -45,11 +45,11 @@ describe('rgba', function () {
             a: 1
         })).toEqual('#01167b');
         expect(rgba.toHex({
-            r: 90,
-            g: 12,
-            b: 311,
-            a: 0.6
-        })).toEqual('#5a0c1371');
+            r: 1,
+            g: 3,
+            b: 5,
+            a: 0.7
+        })).toEqual('#010305b3');
     });
 
     it('.toHsl', function () {