diff --git a/facebook-core/src/main/java/com/facebook/appevents/internal/HashUtils.kt b/facebook-core/src/main/java/com/facebook/appevents/internal/HashUtils.kt
index 015b595f51..b9d4d9db69 100644
--- a/facebook-core/src/main/java/com/facebook/appevents/internal/HashUtils.kt
+++ b/facebook-core/src/main/java/com/facebook/appevents/internal/HashUtils.kt
@@ -20,7 +20,6 @@ import java.lang.reflect.Field
 import java.lang.reflect.InvocationHandler
 import java.lang.reflect.Method
 import java.lang.reflect.Proxy
-import java.math.BigInteger
 import java.security.MessageDigest
 import java.security.cert.CertificateFactory
 import java.util.concurrent.locks.ReentrantLock
@@ -54,7 +53,7 @@ internal object HashUtils {
       } while (numRead != -1)
 
       // Convert byte array to hex string and return result.
-      return BigInteger(1, md.digest()).toString(16)
+      return AppEventUtility.bytesToHex(md.digest())
     }
   }
 
@@ -97,7 +96,7 @@ internal object HashUtils {
                               getTypeMethod.invoke(c) == TYPE_WHOLE_MD5) {
                             val getValueMethod: Method = c.javaClass.getMethod("getValue")
                             val checksumValue = getValueMethod.invoke(c) as ByteArray
-                            resultChecksum = BigInteger(1, checksumValue).toString(16)
+                            resultChecksum = AppEventUtility.bytesToHex(checksumValue)
                             lock.lock()
                             try {
                               checksumReady.signalAll()
diff --git a/facebook-core/src/test/kotlin/com/facebook/appevents/internal/HashUtilsTest.kt b/facebook-core/src/test/kotlin/com/facebook/appevents/internal/HashUtilsTest.kt
index b33a20f637..c556e677b4 100644
--- a/facebook-core/src/test/kotlin/com/facebook/appevents/internal/HashUtilsTest.kt
+++ b/facebook-core/src/test/kotlin/com/facebook/appevents/internal/HashUtilsTest.kt
@@ -28,6 +28,22 @@ class HashUtilsTest : FacebookPowerMockTestCase() {
     assertEquals(expectedChecksum, actualChecksum)
   }
 
+  @Test
+  fun `test computeChecksum preserves leading zeros in digest`() {
+    // MD5("a") = 0cc175b9c0f1b6a831c399e269772661 (one leading zero nibble) and
+    // MD5("jk8ssl") = 0000000018e6137ac2caab16074784a6 (eight leading zero nibbles).
+    // A digest with leading zeros must still render as a full 32-character hex string.
+    val singleZero = File.createTempFile("tempFile.txt", null)
+    singleZero.writeText("a")
+    singleZero.deleteOnExit()
+    assertEquals("0cc175b9c0f1b6a831c399e269772661", HashUtils.computeChecksum(singleZero.path))
+
+    val manyZeros = File.createTempFile("tempFile.txt", null)
+    manyZeros.writeText("jk8ssl")
+    manyZeros.deleteOnExit()
+    assertEquals("0000000018e6137ac2caab16074784a6", HashUtils.computeChecksum(manyZeros.path))
+  }
+
   @Test
   fun `test computeChecksum with empty file`() {
     val tempFile = File.createTempFile("tempFile.txt", null)