diff --git a/src/lib/src/tags/tag-name-format.cpp b/src/lib/src/tags/tag-name-format.cpp
index d206df710..219dc5309 100644
--- a/src/lib/src/tags/tag-name-format.cpp
+++ b/src/lib/src/tags/tag-name-format.cpp
@@ -63,7 +63,7 @@ QString TagNameFormat::formatted(const QString &word, int index) const
 		case TagNameFormat::UpperFirst:
 		{
 			auto res = word.toLower();
-			if (index == 0 || m_caseFormat == TagNameFormat::Upper) {
+			if ((index == 0 || m_caseFormat == TagNameFormat::Upper) && res.length() > 0) {
 				res[0] = res[0].toUpper();
 			}
 			return res;
diff --git a/src/lib/tests/src/tags/tag-name-format-test.cpp b/src/lib/tests/src/tags/tag-name-format-test.cpp
index 0fb7c1449..9cc33f167 100644
--- a/src/lib/tests/src/tags/tag-name-format-test.cpp
+++ b/src/lib/tests/src/tags/tag-name-format-test.cpp
@@ -13,6 +13,7 @@ TEST_CASE("TagNameFormat")
 		REQUIRE(format.formatted(QStringList() << "test") == QString("test"));
 		REQUIRE(format.formatted(QStringList() << "test" << "tag") == QString("test_tag"));
 		REQUIRE(format.formatted(QStringList() << "Test" << "tAG") == QString("test_tag"));
+		REQUIRE(format.formatted(QStringList() << "" << "Test" << "") == QString("_test_"));
 	}
 
 	SECTION("UpperFirst")
@@ -23,6 +24,7 @@ TEST_CASE("TagNameFormat")
 		REQUIRE(format.formatted(QStringList() << "test") == QString("Test"));
 		REQUIRE(format.formatted(QStringList() << "test" << "tag") == QString("Test_tag"));
 		REQUIRE(format.formatted(QStringList() << "Test" << "tAG") == QString("Test_tag"));
+		REQUIRE(format.formatted(QStringList() << "" << "Test" << "") == QString("_test_"));
 	}
 
 	SECTION("Upper")
@@ -33,6 +35,7 @@ TEST_CASE("TagNameFormat")
 		REQUIRE(format.formatted(QStringList() << "test") == QString("Test"));
 		REQUIRE(format.formatted(QStringList() << "test" << "tag") == QString("Test_Tag"));
 		REQUIRE(format.formatted(QStringList() << "Test" << "tAG") == QString("Test_Tag"));
+		REQUIRE(format.formatted(QStringList() << "" << "Test" << "") == QString("_Test_"));
 	}
 
 	SECTION("Caps")
@@ -43,6 +46,7 @@ TEST_CASE("TagNameFormat")
 		REQUIRE(format.formatted(QStringList() << "test") == QString("TEST"));
 		REQUIRE(format.formatted(QStringList() << "test" << "tag") == QString("TEST_TAG"));
 		REQUIRE(format.formatted(QStringList() << "Test" << "tAG") == QString("TEST_TAG"));
+		REQUIRE(format.formatted(QStringList() << "" << "Test" << "") == QString("_TEST_"));
 	}
 
 	SECTION("Unknown")
@@ -53,5 +57,6 @@ TEST_CASE("TagNameFormat")
 		REQUIRE(format.formatted(QStringList() << "test") == QString("test"));
 		REQUIRE(format.formatted(QStringList() << "test" << "tag") == QString("test tag"));
 		REQUIRE(format.formatted(QStringList() << "Test" << "tAG") == QString("Test tAG"));
+		REQUIRE(format.formatted(QStringList() << "" << "Test" << "") == QString(" Test "));
 	}
 }