diff --git a/src/memray/_memray/hooks.cpp b/src/memray/_memray/hooks.cpp
index 170f029ab6..10115350b7 100644
--- a/src/memray/_memray/hooks.cpp
+++ b/src/memray/_memray/hooks.cpp
@@ -196,6 +196,18 @@ free(void* ptr) noexcept
     }
 }
 
+void
+free_sized(void* ptr, size_t size) noexcept
+{
+    memray::intercept::free(ptr);
+}
+
+void
+free_aligned_sized(void* ptr, size_t alignment, size_t size) noexcept
+{
+    memray::intercept::free(ptr);
+}
+
 void*
 realloc(void* ptr, size_t size) noexcept
 {
diff --git a/src/memray/_memray/hooks.h b/src/memray/_memray/hooks.h
index 0b3fef3c2b..4a4d5e9418 100644
--- a/src/memray/_memray/hooks.h
+++ b/src/memray/_memray/hooks.h
@@ -38,6 +38,14 @@
         FOR_EACH_HOOKED_FUNCTION(prctl)
 #endif
 
+#if defined(__STDC_VERSION__) && __STDC_VERSION__ >= 202311L
+#    define MEMRAY_C23_HOOKED_FUNCTIONS                                                                 \
+        FOR_EACH_HOOKED_FUNCTION(free_sized)                                                            \
+        FOR_EACH_HOOKED_FUNCTION(free_aligned_sized)
+#else
+#    define MEMRAY_C23_HOOKED_FUNCTIONS
+#endif
+
 #define MEMRAY_HOOKED_FUNCTIONS                                                                         \
     FOR_EACH_HOOKED_FUNCTION(malloc)                                                                    \
     FOR_EACH_HOOKED_FUNCTION(free)                                                                      \
@@ -51,6 +59,7 @@
     FOR_EACH_HOOKED_FUNCTION(dlopen)                                                                    \
     FOR_EACH_HOOKED_FUNCTION(dlclose)                                                                   \
     FOR_EACH_HOOKED_FUNCTION(PyGILState_Ensure)                                                         \
+    MEMRAY_C23_HOOKED_FUNCTIONS                                                                         \
     MEMRAY_PLATFORM_HOOKED_FUNCTIONS
 
 namespace memray::hooks {
@@ -202,6 +211,12 @@ void*
 mmap64(void* addr, size_t length, int prot, int flags, int fd, off64_t offset) noexcept;
 #endif
 
+void
+free_sized(void* ptr, size_t size) noexcept;
+
+void
+free_aligned_sized(void* ptr, size_t alignment, size_t size) noexcept;
+
 int
 munmap(void* addr, size_t length) noexcept;
 
diff --git a/tests/integration/free_sized_extension/free_sized_test.c b/tests/integration/free_sized_extension/free_sized_test.c
new file mode 100644
index 0000000000..447320fba1
--- /dev/null
+++ b/tests/integration/free_sized_extension/free_sized_test.c
@@ -0,0 +1,150 @@
+#define PY_SSIZE_T_CLEAN
+#include <Python.h>
+
+#include <assert.h>
+#include <stdlib.h>
+#include <dlfcn.h>
+
+__attribute__((weak)) void free_sized(void* ptr, size_t size);
+__attribute__((weak)) void free_aligned_sized(void* ptr, size_t alignment, size_t size);
+
+// Check if C23 functions are available
+static int functions_available = -1;
+
+static void check_functions_available(void) {
+    if (functions_available == -1) {
+        functions_available = (free_sized != NULL && free_aligned_sized != NULL);
+    }
+}
+
+// Structure to hold allocation info
+void*
+test_free_sized(void)
+{
+    void* address;
+
+    check_functions_available();
+    if (!functions_available) {
+        return address;
+    }
+
+    void* ptr = malloc(1024);
+    assert(ptr != NULL);
+
+    address = ptr;
+
+    free_sized(ptr, 1024);
+    return address;
+}
+
+void*
+test_free_aligned_sized(void)
+{
+    void* address;
+
+    check_functions_available();
+    if (!functions_available) {
+        return address;
+    }
+
+    void* ptr = aligned_alloc(64, 1024);
+    assert(ptr != NULL);
+
+    address = ptr;
+
+    free_aligned_sized(ptr, 64, 1024);
+    return address;
+}
+
+void*
+test_both_free_functions(void)
+{
+    void* address;
+
+    check_functions_available();
+    if (!functions_available) {
+        return NULL;
+    }
+
+    void* ptr1 = malloc(512);
+    assert(ptr1 != NULL);
+    free_sized(ptr1, 512);
+
+    void* ptr2 = aligned_alloc(32, 256);
+    assert(ptr2 != NULL);
+    free_aligned_sized(ptr2, 32, 256);
+
+    address = ptr2;
+
+    return address;
+}
+
+PyObject*
+run_free_sized_test(PyObject* self, PyObject* args)
+{
+    check_functions_available();
+    if (!functions_available) {
+        Py_RETURN_NONE;
+    }
+
+    void* address = test_free_sized();
+
+    // Return address for verification
+    PyObject* result = Py_BuildValue("(KII)", address);
+    return result;
+}
+
+PyObject*
+run_free_aligned_sized_test(PyObject* self, PyObject* args)
+{
+    check_functions_available();
+    if (!functions_available) {
+        Py_RETURN_NONE;
+    }
+
+    void* address = test_free_aligned_sized();
+
+    PyObject* result = Py_BuildValue("(KII)", address);
+    return result;
+}
+
+PyObject*
+run_both_tests(PyObject* self, PyObject* args)
+{
+    check_functions_available();
+    if (!functions_available) {
+        Py_RETURN_NONE; // Skip test if functions not available
+    }
+
+    void* address = test_both_free_functions();
+
+    PyObject* result = Py_BuildValue("(KII)", address);
+    return result;
+}
+
+static PyMethodDef
+free_sized_methods[] = {
+    {"run_free_sized_test", run_free_sized_test, METH_NOARGS, "Test free_sized function"},
+    {"run_free_aligned_sized_test", run_free_aligned_sized_test, METH_NOARGS, "Test free_aligned_sized function"},
+    {"run_both_tests", run_both_tests, METH_NOARGS, "Test both free functions"},
+    {NULL, NULL, 0, NULL}
+};
+
+static PyModuleDef
+free_sized_module = {
+    PyModuleDef_HEAD_INIT,
+    "free_sized_test",
+    "Test module for free_sized and free_aligned_sized functions",
+    -1,
+    free_sized_methods,
+    NULL,
+    NULL,
+    NULL,
+    NULL
+};
+
+PyMODINIT_FUNC
+PyInit_free_sized_test(void)
+{
+    return PyModule_Create(&free_sized_module);
+}
diff --git a/tests/integration/free_sized_extension/setup.py b/tests/integration/free_sized_extension/setup.py
new file mode 100644
index 0000000000..597eb7ee62
--- /dev/null
+++ b/tests/integration/free_sized_extension/setup.py
@@ -0,0 +1,14 @@
+from setuptools import Extension
+from setuptools import setup
+
+setup(
+    name="free_sized_extension",
+    ext_modules=[
+        Extension(
+            "free_sized_test",
+            sources=["free_sized_test.c"],
+            language="c",
+            extra_compile_args=["-std=c23"],
+        )
+    ],
+)
diff --git a/tests/integration/test_extensions.py b/tests/integration/test_extensions.py
index c8f6e429ed..27189d965b 100644
--- a/tests/integration/test_extensions.py
+++ b/tests/integration/test_extensions.py
@@ -1,3 +1,4 @@
+import ctypes
 import shutil
 import subprocess
 import sys
@@ -15,6 +16,7 @@
 TEST_MULTITHREADED_EXTENSION = HERE / "multithreaded_extension"
 TEST_MISBEHAVING_EXTENSION = HERE / "misbehaving_extension"
 TEST_RPATH_EXTENSION = HERE / "rpath_extension"
+TEST_FREE_SIZED_EXTENSION = HERE / "free_sized_extension"
 
 
 @pytest.mark.valgrind
@@ -108,7 +110,7 @@ def allocating_function():  # pragma: no cover
     func, filename, line = bottom_frame
     assert func == "allocating_function"
     assert filename.endswith(__file__)
-    assert line == 83
+    assert line == 85
 
     frees = [
         event
@@ -171,7 +173,7 @@ def foo2():
     func, filename, line = bottom_frame
     assert func == "test_extension_that_uses_pygilstate_ensure"
     assert filename.endswith(__file__)
-    assert line == 154
+    assert line == 156
 
     # We should have 2 frames here: this function calling `allocator.valloc`,
     # and `allocator.valloc` calling the C `valloc`.
@@ -186,7 +188,7 @@ def foo2():
     func, filename, line = caller
     assert func == "test_extension_that_uses_pygilstate_ensure"
     assert filename.endswith(__file__)
-    assert line == 155
+    assert line == 157
 
     frees = [
         event
@@ -242,7 +244,7 @@ def allocating_function():
     func, filename, line = bottom_frame
     assert func == "test_native_dlopen"
     assert filename.endswith(__file__)
-    assert line == 226
+    assert line == 228
 
     frees = [
         event
@@ -386,3 +388,99 @@ def test_dlopen_with_rpath(tmpdir, monkeypatch):
         # THEN
         with Tracker(output):
             hello_world()
+
+
+@pytest.mark.skipif(
+    not hasattr(ctypes.CDLL(None), "free_sized"),
+    reason="free_sized not available on this system",
+)
+def test_free_sized_extension(tmpdir, monkeypatch):
+    """Test allocations in a native extension using free_sized and free_aligned_sized."""
+    # GIVEN
+    output = Path(tmpdir) / "test.bin"
+    extension_name = "free_sized_extension"
+    extension_path = tmpdir / extension_name
+    shutil.copytree(TEST_FREE_SIZED_EXTENSION, extension_path)
+
+    # Try to build the extension, skip if compilation fails
+    try:
+        subprocess.run(
+            [
+                sys.executable,
+                str(extension_path / "setup.py"),
+                "build_ext",
+                "--inplace",
+            ],
+            check=True,
+            cwd=extension_path,
+            capture_output=True,
+        )
+    except subprocess.CalledProcessError as e:
+        pytest.skip(f"Failed to compile C23 extension: {e}")
+    except Exception as e:
+        pytest.skip(f"Unexpected error building extension: {e}")
+
+    # WHEN
+    with monkeypatch.context() as ctx:
+        ctx.setattr(sys, "path", [*sys.path, str(extension_path)])
+
+        try:
+            from free_sized_test import run_both_tests  # type: ignore
+        except ImportError as e:
+            pytest.skip(f"Failed to import compiled extension: {e}")
+
+        with Tracker(output):
+            # Get allocation info from the extension
+            result = run_both_tests()
+
+            # Skip test if functions not available (e.g., on macOS)
+            if result is None:
+                pytest.skip("C23 functions not available on this system")
+
+    # THEN
+    records = list(FileReader(output).get_allocation_records())
+    assert records
+
+    # Check that at least 2 allocations from malloc and aligned_alloc
+    mallocs = [
+        record for record in records if record.allocator == AllocatorType.ALIGNED_ALLOC
+    ]
+    assert len(mallocs) >= 2
+
+    # Check that corresponding FREE records - this verifies hooks are working!
+    mallocs_addr = {record.address for record in mallocs}
+    frees = [
+        record
+        for record in records
+        if record.address in mallocs_addr and record.allocator == AllocatorType.FREE
+    ]
+    assert len(frees) == len(mallocs)
+
+    assert all(len(malloc.stack_trace()) == 0 for malloc in mallocs)
+    assert all(len(free.stack_trace()) == 0 for free in frees)
+
+    # Verify that the specific addresses returned by the extension were tracked
+    if result is not None:
+        expected_address = result[0]
+
+        # Find the allocation record for this address
+        matching_allocs = [
+            record
+            for record in records
+            if record.address == expected_address
+            and record.allocator == AllocatorType.ALIGNED_ALLOC
+        ]
+        assert (
+            len(matching_allocs) >= 1
+        ), f"Expected allocation at address {expected_address} not found"
+
+        # Find the corresponding free record
+        matching_frees = [
+            record
+            for record in records
+            if record.address == expected_address
+            and record.allocator == AllocatorType.FREE
+        ]
+        assert (
+            len(matching_frees) >= 1
+        ), f"Expected free at address {expected_address} not found"