diff --git a/src/corelib/io/qdataurl.cpp b/src/corelib/io/qdataurl.cpp
index c5ecca8fb82..2d2426e8ea5 100644
--- a/src/corelib/io/qdataurl.cpp
+++ b/src/corelib/io/qdataurl.cpp
@@ -20,8 +20,6 @@ Q_CORE_EXPORT bool qDecodeDataUrl(const QUrl &uri, QString &mimeType, QByteArray
     if (uri.scheme() != "data"_L1 || !uri.host().isEmpty())
         return false;
 
-    mimeType = QStringLiteral("text/plain;charset=US-ASCII");
-
     // the following would have been the correct thing, but
     // reality often differs from the specification. People have
     // data: URIs with ? and #
@@ -56,6 +54,8 @@ Q_CORE_EXPORT bool qDecodeDataUrl(const QUrl &uri, QString &mimeType, QByteArray
 
         if (!data.isEmpty())
             mimeType = textPlain + QLatin1StringView(data.trimmed());
+        else
+            mimeType = QStringLiteral("text/plain;charset=US-ASCII");
     }
 
     return true;
diff --git a/tests/auto/corelib/io/qdataurl/tst_qdataurl.cpp b/tests/auto/corelib/io/qdataurl/tst_qdataurl.cpp
index 7fbf4be56b9..39d860adaf7 100644
--- a/tests/auto/corelib/io/qdataurl/tst_qdataurl.cpp
+++ b/tests/auto/corelib/io/qdataurl/tst_qdataurl.cpp
@@ -31,8 +31,7 @@ void tst_QDataUrl::decode_data()
     row("malformed-host", "data://test.com", false);
     row("malformed-host2", "data://text/plain;charset=ISO-8859-1", false);
     row("malformed-host3", "data://test.com/,", false);
-    row("emptyData", "data:text/plain", true,
-        "text/plain;charset=US-ASCII"_L1);
+    row("emptyData", "data:text/plain", true);
     row("emptyData-default-mimetype", "data:,", true,
         "text/plain;charset=US-ASCII"_L1, "");
     row("emptyData-only-charset", "data:charset=ISO-8859-1,", true,