diff --git a/core/thread.c b/core/thread.c
index cd97c38d607f..cb828b6df4d8 100644
--- a/core/thread.c
+++ b/core/thread.c
@@ -178,9 +178,6 @@ uintptr_t measure_stack_free_internal(const char *stack, size_t size)
     uintptr_t *stackp = (uintptr_t *)(uintptr_t)stack;
     uintptr_t end = (uintptr_t)stack + size;
 
-    /* better be safe than sorry: align end of stack just in case */
-    end &= (sizeof(uintptr_t) - 1);
-
     /* assume that the stack grows "downwards" */
     while (((uintptr_t)stackp < end) && (*stackp == (uintptr_t)stackp)) {
         stackp++;
diff --git a/tests/core/thread_stack_alignment/tests/01-run.py b/tests/core/thread_stack_alignment/tests/01-run.py
index 9f47280b333d..9a7c395a71f4 100755
--- a/tests/core/thread_stack_alignment/tests/01-run.py
+++ b/tests/core/thread_stack_alignment/tests/01-run.py
@@ -24,6 +24,7 @@ def testfunc(child):
         child.expect(r"(\{[^\n\r]*\})\r\n")
         stats = json.loads(child.match.group(1))["threads"][0]
         assert stats["name"] == "test"
+        assert stats["stack_used"] < stats["stack_size"]
         if stack_used_max < stats["stack_used"]:
             stack_used_max = stats["stack_used"]
         if stack_used_min > stats["stack_used"]: