diff --git a/README.md b/README.md
index 08d4aa4..657da8f 100644
--- a/README.md
+++ b/README.md
@@ -1,4 +1,4 @@
-Kalkulator BMI
+Kalkulator BMI Oleh Fadhlul Wafi 202310715188 F5A5
 ===============
 
 Silahkan kembangkan aplikasi ini untuk melakukan perhitungan BMI
diff --git a/app/src/main/java/com/example/tiptime/MainActivity.kt b/app/src/main/java/com/example/tiptime/MainActivity.kt
index d0fdd80..82edf45 100644
--- a/app/src/main/java/com/example/tiptime/MainActivity.kt
+++ b/app/src/main/java/com/example/tiptime/MainActivity.kt
@@ -185,12 +185,25 @@ fun RoundTheTipRow(
  *
  * Catatan: tambahkan unit test untuk kalkulasi BMI ini
  */
-private fun calculateBMI(BmiHeight: Double, BmiWeight: Double = 15.0, roundUp: Boolean): String {
-    var bmi = BmiWeight / 100 * BmiHeight
-    if (roundUp) {
-        bmi = kotlin.math.ceil(bmi)
+//private fun calculateBMI(BmiHeight: Double, BmiWeight: Double = 15.0, roundUp: Boolean): String {
+//    var bmi = BmiWeight / 100 * BmiHeight
+//    if (roundUp) {
+//        bmi = kotlin.math.ceil(bmi)
+//    }
+//    return NumberFormat.getNumberInstance().format(bmi)
+//}
+private fun calculateBMI(BmiHeight: Double, BmiWeight: Double, useUSC: Boolean): String {
+    if (BmiHeight <= 0 || BmiWeight <= 0) return "0.0"
+
+    val bmi = if (useUSC) {
+        // Rumus USC: 703 * weight(lb) / height(in)^2
+        703 * BmiWeight / (BmiHeight * BmiHeight)
+    } else {
+        // Rumus SI: weight(kg) / (height(m))^2
+        BmiWeight / ((BmiHeight / 100) * (BmiHeight / 100))
     }
-    return NumberFormat.getNumberInstance().format(bmi)
+
+    return String.format("%.2f", bmi)
 }
 /**
  * Calculates the BMI Category
@@ -198,13 +211,33 @@ private fun calculateBMI(BmiHeight: Double, BmiWeight: Double = 15.0, roundUp: B
  * Catatan: tambahkan unit test untuk kalkulasi BMI ini
  */
 
-private fun calculateBMICategory(BmiHeight: Double, BmiWeight: Double = 15.0, roundUp: Boolean): String {
-    var bmi = BmiWeight / 100 * BmiHeight
-    if (roundUp) {
-        bmi = kotlin.math.ceil(bmi)
+//private fun calculateBMICategory(BmiHeight: Double, BmiWeight: Double = 15.0, roundUp: Boolean): String {
+//    var bmi = BmiWeight / 100 * BmiHeight
+//    if (roundUp) {
+//        bmi = kotlin.math.ceil(bmi)
+//    }
+//    return NumberFormat.getNumberInstance().format(bmi)
+//}
+/**
+ * Menentukan kategori BMI berdasarkan nilai BMI
+ */
+private fun calculateBMICategory(BmiHeight: Double, BmiWeight: Double, useUSC: Boolean): String {
+    if (BmiHeight <= 0 || BmiWeight <= 0) return "Input tidak valid"
+
+    val bmiValue = if (useUSC) {
+        703 * BmiWeight / (BmiHeight * BmiHeight)
+    } else {
+        BmiWeight / ((BmiHeight / 100) * (BmiHeight / 100))
+    }
+
+    return when {
+        bmiValue < 18.5 -> "Underweight"
+        bmiValue < 25 -> "Normal"
+        bmiValue < 30 -> "Overweight"
+        else -> "Obesity"
     }
-    return NumberFormat.getNumberInstance().format(bmi)
 }
+
 @Preview(showBackground = true)
 @Composable
 fun TipTimeLayoutPreview() {