diff --git a/src/minirechner.c b/src/minirechner.c
index 6a133f3..cbc13ef 100644
--- a/src/minirechner.c
+++ b/src/minirechner.c
@@ -25,4 +25,9 @@ float dividieren(float a, float b) {
     else {
         return a / b;
     }
+}
+
+//rest
+float rest(float a, float b) {
+    return fmod(a, b);
 }
\ No newline at end of file
diff --git a/src/minirechner.h b/src/minirechner.h
index 8c4466f..a2c989f 100644
--- a/src/minirechner.h
+++ b/src/minirechner.h
@@ -5,5 +5,6 @@ float addieren(float a, float b);
 float subtrahieren(float a, float b);
 float multiplizieren(float a, float b);
 float dividieren(float a, float b);
+float rest(float a, float b);
 
 #endif // MINIRECHNER_H
diff --git a/test/test_minirechner.c b/test/test_minirechner.c
index 88e1df2..8df2c71 100644
--- a/test/test_minirechner.c
+++ b/test/test_minirechner.c
@@ -100,4 +100,11 @@ void test_minitaschenrechner_0_durch_5(void)
     TEST_ASSERT_EQUAL(0, result);
 }
 
+// test rest
+void test_minitaschenrechner_14_rest_5(void)
+{
+    float result = rest(14, 5);
+    TEST_ASSERT_EQUAL(4, result);
+}
+
 #endif // TEST