diff --git a/library/common/src/main/java/com/google/android/exoplayer2/util/Util.java b/library/common/src/main/java/com/google/android/exoplayer2/util/Util.java
index 2d643673be..2e3e3d8567 100644
--- a/library/common/src/main/java/com/google/android/exoplayer2/util/Util.java
+++ b/library/common/src/main/java/com/google/android/exoplayer2/util/Util.java
@@ -760,16 +760,6 @@ public final class Util {
     return c == '\n' || c == '\r';
   }
 
-  /**
-   * Converts text to upper case using {@link Locale#US}.
-   *
-   * @param text The text to convert.
-   * @return The upper case text, or null if {@code text} is null.
-   */
-  public static @PolyNull String toUpperInvariant(@PolyNull String text) {
-    return text == null ? text : text.toUpperCase(Locale.US);
-  }
-
   /**
    * Formats a string using {@link Locale#US}.
    *
@@ -2151,11 +2141,11 @@ public final class Util {
       if (telephonyManager != null) {
         String countryCode = telephonyManager.getNetworkCountryIso();
         if (!TextUtils.isEmpty(countryCode)) {
-          return toUpperInvariant(countryCode);
+          return Ascii.toUpperCase(countryCode);
         }
       }
     }
-    return toUpperInvariant(Locale.getDefault().getCountry());
+    return Ascii.toUpperCase(Locale.getDefault().getCountry());
   }
 
   /**
diff --git a/library/core/src/main/java/com/google/android/exoplayer2/upstream/DefaultBandwidthMeter.java b/library/core/src/main/java/com/google/android/exoplayer2/upstream/DefaultBandwidthMeter.java
index 8232d90668..1c0b3f2642 100644
--- a/library/core/src/main/java/com/google/android/exoplayer2/upstream/DefaultBandwidthMeter.java
+++ b/library/core/src/main/java/com/google/android/exoplayer2/upstream/DefaultBandwidthMeter.java
@@ -25,6 +25,7 @@ import com.google.android.exoplayer2.util.Clock;
 import com.google.android.exoplayer2.util.NetworkTypeObserver;
 import com.google.android.exoplayer2.util.SlidingPercentile;
 import com.google.android.exoplayer2.util.Util;
+import com.google.common.base.Ascii;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableListMultimap;
 import com.google.common.collect.ImmutableMap;
@@ -170,7 +171,7 @@ public final class DefaultBandwidthMeter implements BandwidthMeter, TransferList
      */
     public Builder setInitialBitrateEstimate(String countryCode) {
       initialBitrateEstimates =
-          getInitialBitrateEstimatesForCountry(Util.toUpperInvariant(countryCode));
+          getInitialBitrateEstimatesForCountry(Ascii.toUpperCase(countryCode));
       return this;
     }
 
diff --git a/library/hls/src/test/java/com/google/android/exoplayer2/source/hls/playlist/HlsMediaPlaylistParserTest.java b/library/hls/src/test/java/com/google/android/exoplayer2/source/hls/playlist/HlsMediaPlaylistParserTest.java
index 48f6a06b14..7cc9a75c1a 100644
--- a/library/hls/src/test/java/com/google/android/exoplayer2/source/hls/playlist/HlsMediaPlaylistParserTest.java
+++ b/library/hls/src/test/java/com/google/android/exoplayer2/source/hls/playlist/HlsMediaPlaylistParserTest.java
@@ -135,7 +135,7 @@ public class HlsMediaPlaylistParserTest {
         .isEqualTo("https://priv.example.com/key.php?r=2682");
     // 0xA7A == 2682.
     assertThat(segment.encryptionIV).isNotNull();
-    assertThat(Util.toUpperInvariant(segment.encryptionIV)).isEqualTo("A7A");
+    assertThat(segment.encryptionIV).ignoringCase().isEqualTo("A7A");
     assertThat(segment.byteRangeLength).isEqualTo(51740);
     assertThat(segment.byteRangeOffset).isEqualTo(2147586650L);
     assertThat(segment.url).isEqualTo("https://priv.example.com/fileSequence2682.ts");
@@ -148,7 +148,7 @@ public class HlsMediaPlaylistParserTest {
         .isEqualTo("https://priv.example.com/key.php?r=2682");
     // 0xA7B == 2683.
     assertThat(segment.encryptionIV).isNotNull();
-    assertThat(Util.toUpperInvariant(segment.encryptionIV)).isEqualTo("A7B");
+    assertThat(segment.encryptionIV).ignoringCase().isEqualTo("A7B");
     assertThat(segment.byteRangeLength).isEqualTo(C.LENGTH_UNSET);
     assertThat(segment.byteRangeOffset).isEqualTo(0);
     assertThat(segment.url).isEqualTo("https://priv.example.com/fileSequence2683.ts");