diff --git a/tests/CMakeLists.txt b/tests/CMakeLists.txt
index a1b7250fa..4a2e33a63 100644
--- a/tests/CMakeLists.txt
+++ b/tests/CMakeLists.txt
@@ -69,3 +69,28 @@ endif()
 
 include(GoogleTest)
 gtest_discover_tests(vulkan_tools_tests DISCOVERY_TIMEOUT 100)
+
+# vulkaninfo command line parsing: output format flags are mutually exclusive.
+# Argument parsing happens before any Vulkan call, so these tests do not need a driver.
+if (TARGET vulkaninfo)
+    set(VULKANINFO_CONFLICTING_FORMATS
+        "--html|--json"
+        "--json|--html"
+        "--text|--html"
+        "--summary|--text"
+        "--summary|-j"
+        "--json=0|--summary"
+        "--vkconfig_output|--html"
+    )
+    # Pairs use '|' as the separator since CMake flattens nested ';' lists
+    foreach(FORMAT_PAIR_STRING IN LISTS VULKANINFO_CONFLICTING_FORMATS)
+        string(REPLACE "|" ";" FORMAT_PAIR "${FORMAT_PAIR_STRING}")
+        string(REPLACE "|" "_" TEST_SUFFIX "${FORMAT_PAIR_STRING}")
+        string(REGEX REPLACE "[-=]" "" TEST_SUFFIX "${TEST_SUFFIX}")
+        set(TEST_NAME vulkaninfo_rejects_conflicting_formats_${TEST_SUFFIX})
+        add_test(NAME ${TEST_NAME} COMMAND $<TARGET_FILE:vulkaninfo> ${FORMAT_PAIR})
+        set_tests_properties(${TEST_NAME} PROPERTIES
+            PASS_REGULAR_EXPRESSION "Only one output format may be specified"
+        )
+    endforeach()
+endif()
diff --git a/vulkaninfo/vulkaninfo.cpp b/vulkaninfo/vulkaninfo.cpp
index df7ce022b..3d9fc5423 100644
--- a/vulkaninfo/vulkaninfo.cpp
+++ b/vulkaninfo/vulkaninfo.cpp
@@ -1249,6 +1249,8 @@ enum class OutputCategory { text, html, profile_json, vkconfig_output, summary }
 const char *help_message_body =
     "OPTIONS:\n"
     "[-h, --help]         Print this help.\n"
+    "Note: --summary, --text, --html, --json, and --vkconfig_output select the output\n"
+    "      format and are mutually exclusive; specify at most one.\n"
     "[--summary]          Show a summary of the instance and GPU's on a system.\n"
     "[-o <filename>, --output <filename>]\n"
     "                     Print output to a new file whose name is specified by filename.\n"
@@ -1315,12 +1317,18 @@ struct ParsedResults {
 util::vulkaninfo_optional<ParsedResults> parse_arguments(int argc, char **argv, std::string executable_name) {
     ParsedResults results{};
     results.default_filename = APP_SHORT_NAME ".txt";
+    // Output formats are mutually exclusive, so record every format requested and reject more than one distinct format.
+    std::set<OutputCategory> requested_categories;
+    auto set_output_category = [&](OutputCategory category) {
+        results.output_category = category;
+        requested_categories.insert(category);
+    };
     for (int i = 1; i < argc; ++i) {
         // A internal-use-only format for communication with the Vulkan Configurator tool
         // Usage "--vkconfig_output <path>"
         // -o can be used to specify the filename instead
         if (0 == strcmp("--vkconfig_output", argv[i])) {
-            results.output_category = OutputCategory::vkconfig_output;
+            set_output_category(OutputCategory::vkconfig_output);
             results.print_to_file = true;
             results.default_filename = APP_SHORT_NAME ".json";
             if (argc > (i + 1) && argv[i + 1][0] != '-') {
@@ -1332,6 +1340,7 @@ util::vulkaninfo_optional<ParsedResults> parse_arguments(int argc, char **argv,
                 ++i;
             }
         } else if (strncmp("--json", argv[i], 6) == 0 || strncmp(argv[i], "-j", 2) == 0) {
+            set_output_category(OutputCategory::profile_json);
             if (strlen(argv[i]) > 7 && strncmp("--json=", argv[i], 7) == 0) {
                 results.selected_gpu = static_cast<uint32_t>(strtol(argv[i] + 7, nullptr, 10));
                 results.has_selected_gpu = true;
@@ -1340,16 +1349,15 @@ util::vulkaninfo_optional<ParsedResults> parse_arguments(int argc, char **argv,
                 results.selected_gpu = static_cast<uint32_t>(strtol(argv[i] + 3, nullptr, 10));
                 results.has_selected_gpu = true;
             }
-            results.output_category = OutputCategory::profile_json;
             results.default_filename = APP_SHORT_NAME ".json";
             results.print_to_file = true;
         } else if (strcmp(argv[i], "--summary") == 0) {
-            results.output_category = OutputCategory::summary;
+            set_output_category(OutputCategory::summary);
         } else if (strcmp(argv[i], "--text") == 0) {
-            results.output_category = OutputCategory::text;
+            set_output_category(OutputCategory::text);
             results.default_filename = APP_SHORT_NAME ".txt";
         } else if (strcmp(argv[i], "--html") == 0) {
-            results.output_category = OutputCategory::html;
+            set_output_category(OutputCategory::html);
             results.print_to_file = true;
             results.default_filename = APP_SHORT_NAME ".html";
         } else if (strcmp(argv[i], "--show-all") == 0) {
@@ -1382,6 +1390,11 @@ util::vulkaninfo_optional<ParsedResults> parse_arguments(int argc, char **argv,
             return {};
         }
     }
+    if (requested_categories.size() > 1) {
+        std::cerr << "Error: --summary, --text, --html, --json, and --vkconfig_output cannot be combined. "
+                     "Only one output format may be specified.\n";
+        return {};
+    }
     return results;
 }
 
diff --git a/vulkaninfo/vulkaninfo.md b/vulkaninfo/vulkaninfo.md
index 17b4a8b69..686d37dce 100644
--- a/vulkaninfo/vulkaninfo.md
+++ b/vulkaninfo/vulkaninfo.md
@@ -61,6 +61,8 @@ USAGE:
 
 OPTIONS:
 [-h, --help]        Print this help.
+Note: --summary, --text, --html, and --json select the output format and are
+      mutually exclusive; specify at most one.
 [--summary]         Show a summary of the instance and GPU's on a system.
 [-o <filename>, --output <filename>]
                     Print output to a new file whose name is specified by filename.