diff --git a/src/model/Color.ts b/src/model/Color.ts
index e247a4260..426c2a5a0 100644
--- a/src/model/Color.ts
+++ b/src/model/Color.ts
@@ -119,7 +119,8 @@ export class Color {
                             throw new FormatError('No values specified for rgb/rgba function');
                         }
 
-                        const numbers = json.substring(start + 1, end - start - 1).split(',');
+                        const numbers = json.substring(start + 1, end).split(',');
+
                         if (numbers.length === 3) {
                             return new Color(parseInt(numbers[0]), parseInt(numbers[1]), parseInt(numbers[2]));
                         }
diff --git a/test/model/Color.test.ts b/test/model/Color.test.ts
new file mode 100644
index 000000000..b4714b481
--- /dev/null
+++ b/test/model/Color.test.ts
@@ -0,0 +1,9 @@
+import { Color } from "@src/model/Color";
+
+describe('ColorTests', () => {
+  it('fromJson-rgb', () => {
+    const color = Color.fromJson('rgb(0,0,0)');
+
+    expect(color!.rgba).toEqual('#000000');
+  });
+});