diff --git a/libc/test/UnitTest/LibcTest.cpp b/libc/test/UnitTest/LibcTest.cpp
--- a/libc/test/UnitTest/LibcTest.cpp
+++ b/libc/test/UnitTest/LibcTest.cpp
@@ -13,6 +13,13 @@
 #include "src/__support/UInt128.h"
 #include "test/UnitTest/TestLogger.h"
 
+#if __STDC_HOSTED__
+#include <time.h>
+#else
+static long clock() { return 0; }
+#define CLOCKS_PER_SEC 1
+#endif
+
 namespace __llvm_libc {
 namespace testing {
 
@@ -162,19 +169,30 @@
       continue;
     }
     tlog << GREEN << "[ RUN      ] " << RESET << TestName << '\n';
+    const auto start_time = clock();
     RunContext Ctx;
     T->SetUp();
     T->setContext(&Ctx);
     T->Run();
     T->TearDown();
     auto Result = Ctx.status();
+    const auto duration = clock() - start_time;
+    const auto elapsed_ms =
+        static_cast<uint64_t>(duration * 1000 / CLOCKS_PER_SEC);
     switch (Result) {
     case RunContext::Result_Fail:
       tlog << RED << "[  FAILED  ] " << RESET << TestName << '\n';
       ++FailCount;
       break;
     case RunContext::Result_Pass:
+#if __STDC_HOSTED__
+      const auto seconds = static_cast<uint64_t>(elapsed_ms / 1000);
+      const auto frac = static_cast<uint64_t>(elapsed_ms % 1000);
+      tlog << GREEN << "[       OK ] " << RESET << TestName << " (took "
+           << elapsed_ms << " ms)\n";
+#else
       tlog << GREEN << "[       OK ] " << RESET << TestName << '\n';
+#endif
       break;
     }
     ++TestCount;