diff --git a/libc/docs/headers/complex.rst b/libc/docs/headers/complex.rst
index 272cf00c883bc..7195f2695457e 100644
--- a/libc/docs/headers/complex.rst
+++ b/libc/docs/headers/complex.rst
@@ -10,7 +10,7 @@ Macros
 +-----------+------------------+-----------------+------------------------+----------------------+------------------------+------------------------+----------------------------+
 | <Func>    | <Func_f> (float) | <Func> (double) | <Func_l> (long double) | <Func_f16> (float16) | <Func_f128> (float128) | C23 Definition Section | C23 Error Handling Section |
 +===========+==================+=================+========================+======================+========================+========================+============================+
-| CMPLX     |                  |                 |                        |                      |                        | 7.3.9.3                | N/A                        |
+| CMPLX     | |check|          | |check|         | |check|                | |check|              | |check|                | 7.3.9.3                | N/A                        |
 +-----------+------------------+-----------------+------------------------+----------------------+------------------------+------------------------+----------------------------+
 
 Functions
diff --git a/libc/include/llvm-libc-macros/CMakeLists.txt b/libc/include/llvm-libc-macros/CMakeLists.txt
index 7aa549ddc75d9..055e11f958e02 100644
--- a/libc/include/llvm-libc-macros/CMakeLists.txt
+++ b/libc/include/llvm-libc-macros/CMakeLists.txt
@@ -61,12 +61,6 @@ add_macro_header(
     fcntl-macros.h
 )
 
-add_macro_header(
-  complex_macros
-  HDR
-    complex-macros.h
-)
-
 add_macro_header(
   features_macros
   HDR
@@ -103,6 +97,14 @@ add_macro_header(
     float16-macros.h
 )
 
+add_macro_header(
+  complex_macros
+  HDR
+    complex-macros.h
+  DEPENDS
+    .float16_macros
+)
+
 add_macro_header(
   limits_macros
   HDR
diff --git a/libc/include/llvm-libc-macros/complex-macros.h b/libc/include/llvm-libc-macros/complex-macros.h
index 427c68d289e0b..fdcc9c7831dd1 100644
--- a/libc/include/llvm-libc-macros/complex-macros.h
+++ b/libc/include/llvm-libc-macros/complex-macros.h
@@ -9,6 +9,8 @@
 #ifndef __LLVM_LIBC_MACROS_COMPLEX_MACROS_H
 #define __LLVM_LIBC_MACROS_COMPLEX_MACROS_H
 
+#include "float16-macros.h"
+
 #ifndef __STDC_NO_COMPLEX__
 
 #define __STDC_VERSION_COMPLEX_H__ 202311L
@@ -19,6 +21,18 @@
 
 // TODO: Add imaginary macros once GCC or Clang support _Imaginary builtin-type.
 
+#define CMPLX(x, y) __builtin_complex((double)(x), (double)(y))
+#define CMPLXF(x, y) __builtin_complex((float)(x), (float)(y))
+#define CMPLXL(x, y) __builtin_complex((long double)(x), (long double)(y))
+
+#ifdef LIBC_TYPES_HAS_FLOAT16
+#define CMPLXF16(x, y) __builtin_complex((float16)(x), (float16)(y))
+#endif // LIBC_TYPES_HAS_FLOAT16
+
+#ifdef LIBC_TYPES_HAS_FLOAT128
+#define CMPLXF128(x, y) __builtin_complex((float128)(x), (float128)(y))
+#endif // LIBC_TYPES_HAS_FLOAT128
+
 #endif
 
 #endif // __LLVM_LIBC_MACROS_COMPLEX_MACROS_H
diff --git a/libc/test/include/complex_test.cpp b/libc/test/include/complex_test.cpp
index da833fb527381..869d2a935986e 100644
--- a/libc/test/include/complex_test.cpp
+++ b/libc/test/include/complex_test.cpp
@@ -17,3 +17,12 @@ TEST(LlvmLibcComplexTest, VersionMacro) {
 TEST(LlvmLibcComplexTest, IMacro) { EXPECT_CFP_EQ(1.0fi, I); }
 
 TEST(LlvmLibcComplexTest, _Complex_IMacro) { EXPECT_CFP_EQ(1.0fi, _Complex_I); }
+
+TEST(LlvmLibcComplexTest, CMPLXMacro) {
+  EXPECT_CFP_EQ(CMPLX(0, 1.0), I);
+  EXPECT_CFP_EQ(CMPLX(1.0, 0), 1.0);
+  EXPECT_CFP_EQ(CMPLXF(0, 1.0f), I);
+  EXPECT_CFP_EQ(CMPLXF(1.0f, 0), 1.0f);
+  EXPECT_CFP_EQ(CMPLXL(0, 1.0l), I);
+  EXPECT_CFP_EQ(CMPLXL(1.0l, 0), 1.0l);
+}