diff --git a/maps-kt-core/src/commonMain/kotlin/center/sciprog/maps/coordinates/Angle.kt b/maps-kt-core/src/commonMain/kotlin/center/sciprog/maps/coordinates/Angle.kt
index c0245ba..0f1f823 100644
--- a/maps-kt-core/src/commonMain/kotlin/center/sciprog/maps/coordinates/Angle.kt
+++ b/maps-kt-core/src/commonMain/kotlin/center/sciprog/maps/coordinates/Angle.kt
@@ -85,8 +85,8 @@ public val Number.degrees: Degrees get() = Degrees(toDouble())
  * Normalized angle to (0, 2PI) for radians or (0, 360) for degrees.
  */
 public fun Angle.normalized(): Angle = when (this) {
-    is Degrees -> (value + 180.0).rem(360.0).degrees
-    is Radians -> (value + PI).rem(PI * 2).radians
+    is Degrees -> value.mod(360.0).degrees
+    is Radians -> value.mod(PI * 2).radians
 }
 
 public fun abs(angle: Angle): Angle = if (angle < Angle.zero) -angle else angle
\ No newline at end of file
diff --git a/maps-kt-core/src/commonTest/kotlin/center/sciprog/maps/coordinates/AngleTest.kt b/maps-kt-core/src/commonTest/kotlin/center/sciprog/maps/coordinates/AngleTest.kt
new file mode 100644
index 0000000..53480fc
--- /dev/null
+++ b/maps-kt-core/src/commonTest/kotlin/center/sciprog/maps/coordinates/AngleTest.kt
@@ -0,0 +1,12 @@
+package center.sciprog.maps.coordinates
+
+import kotlin.test.Test
+import kotlin.test.assertEquals
+
+class AngleTest {
+    @Test
+    fun normalization(){
+        assertEquals(30.degrees, 390.degrees.normalized())
+        assertEquals(30.degrees, (-330).degrees.normalized())
+    }
+}
\ No newline at end of file