diff --git a/libc/config/linux/x86_64/entrypoints.txt b/libc/config/linux/x86_64/entrypoints.txt
--- a/libc/config/linux/x86_64/entrypoints.txt
+++ b/libc/config/linux/x86_64/entrypoints.txt
@@ -27,6 +27,7 @@
     libc.src.string.strcat
     libc.src.string.strlen
     libc.src.string.strcmp
+    libc.src.string.strdup
 
     # sys/mman.h entrypoints
     libc.src.sys.mman.mmap
diff --git a/libc/src/string/CMakeLists.txt b/libc/src/string/CMakeLists.txt
--- a/libc/src/string/CMakeLists.txt
+++ b/libc/src/string/CMakeLists.txt
@@ -44,6 +44,18 @@
     libc.include.string
 )
 
+add_entrypoint_object(
+  strdup
+  SRCS
+    strdup.cpp
+  HDRS
+    strdup.h
+  DEPENDS
+    .memcpy
+    .strlen
+    libc.include.string
+)
+
 # Helper to define a function with multiple implementations
 # - Computes flags to satisfy required/rejected features and arch,
 # - Declares an entry point,
diff --git a/libc/src/string/strdup.h b/libc/src/string/strdup.h
new file mode 100644
--- /dev/null
+++ b/libc/src/string/strdup.h
@@ -0,0 +1,20 @@
+//===-- Implementation header for strdup ------------------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_LIBC_SRC_STRING_STRDUP_H
+#define LLVM_LIBC_SRC_STRING_STRDUP_H
+
+#include "include/string.h"
+
+namespace __llvm_libc {
+
+char *strdup(const char *src);
+
+} // namespace __llvm_libc
+
+#endif // LLVM_LIBC_SRC_STRING_STRDUP_H
diff --git a/libc/src/string/strdup.cpp b/libc/src/string/strdup.cpp
new file mode 100644
--- /dev/null
+++ b/libc/src/string/strdup.cpp
@@ -0,0 +1,24 @@
+//===-- Implementation of strdup ------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "src/string/strdup.h"
+#include "src/string/memcpy.h"
+#include "src/string/strlen.h"
+#include <stddef.h>
+
+namespace __llvm_libc {
+
+char *LLVM_LIBC_ENTRYPOINT(strdup)(const char *src) {
+  const size_t length = __llvm_libc::strlen(s) + 1;
+  char *duplicate = new char[length];
+  if (!duplicate)
+    return NULL;
+  return reinterpret_cast<char *>(memcpy(duplicate, s, length));
+}
+
+} // namespace __llvm_libc
diff --git a/libc/test/src/string/CMakeLists.txt b/libc/test/src/string/CMakeLists.txt
--- a/libc/test/src/string/CMakeLists.txt
+++ b/libc/test/src/string/CMakeLists.txt
@@ -42,6 +42,16 @@
     libc.src.string.strcmp
 )
 
+add_libc_unittest(
+  strdup_test
+  SUITE
+    libc_string_unittests
+  SRCS
+    strdup_test.cpp
+  DEPENDS
+    libc.src.string.strdup
+)
+
 # Tests all implementations that can run on the host.
 function(add_libc_multi_impl_test name)
   get_property(fq_implementations GLOBAL PROPERTY ${name}_implementations)
diff --git a/libc/test/src/string/strdup_test.cpp b/libc/test/src/string/strdup_test.cpp
new file mode 100644
--- /dev/null
+++ b/libc/test/src/string/strdup_test.cpp
@@ -0,0 +1,27 @@
+//===-- Unittests for strdup ----------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "src/string/strdup.h"
+
+TEST(StrDupTest, NullTerminatorIsIncluded) {
+  const char *s = "foobar";
+  const char *dup = __llvm_libc::strdup(s);
+  ASSERT_STREQ(s, dup);
+}
+
+TEST(StrDupTest, DuplicateOfEmptyStringShouldBeEmptyString) {
+  const char *empty = "";
+  const char *dup = __llvm_libc::strdup(empty);
+  ASSERT_STREQ(empty, dup);
+}
+
+TEST(StrDupTest, DuplicateShouldBeEqualToOriginalString) {
+  const char *s = "abcd1234";
+  const char *dup = __llvm_libc::strdup(s);
+  ASSERT_STREQ(s, dup);
+}