diff --git a/assert.py b/assert.py
new file mode 100644
index 0000000..9d751aa
--- /dev/null
+++ b/assert.py
@@ -0,0 +1,38 @@
+# /// script
+# requires-python = ">=3.14"
+# dependencies = ["imagehash<5"]
+# ///
+
+import json
+
+import imagehash
+from PIL import Image
+
+Image.MAX_IMAGE_PIXELS = None
+
+
+def calculate_hash(filename: str) -> imagehash.ImageHash:
+    im = Image.open(filename)
+    return imagehash.phash(im)
+
+
+def test_hashes(subtests):
+    with open("answer.json", "r") as file:
+        answers = json.load(file)
+        for test in answers.get("tests", []):
+            name = test.get("name")
+            hash = imagehash.hex_to_hash(test.get("p_hash"))
+            with subtests.test(msg=name):
+                actual = calculate_hash(name)
+                assert actual - hash < 3
+
+
+def test_sizes(subtests):
+    with open("answer.json", "r") as file:
+        answers = json.load(file)
+        for test in answers.get("tests", []):
+            name = test.get("name")
+            size = test.get("img_size")
+            with subtests.test(msg=name):
+                im = Image.open(name)
+                assert im.size == tuple(size)