diff --git a/.custom-format.py b/.custom-format.py
index e7e2892b..9899ea9d 100755
--- a/.custom-format.py
+++ b/.custom-format.py
@@ -21,12 +21,15 @@ import os
 # import re # TODO: for future use
 import shutil
 import importlib.metadata
+import hashlib
 
 # string_re = re.compile('(\\"(\\\\.|[^"\\\\])*\\")') # TODO: for future use
 
 CURRENT_LLVM = os.getenv('LLVM_VERSION', 18)
 CLANG_FORMAT_BIN = os.getenv("CLANG_FORMAT_BIN", "")
 
+FORMAT_CACHE_DIR = '.format-cache'
+os.makedirs(FORMAT_CACHE_DIR, exist_ok=True)
 
 def check_clang_format_pip_version():
     """
@@ -69,6 +72,8 @@ to install via pip.")
 if CLANG_FORMAT_PIP:
     CLANG_FORMAT_BIN = shutil.which("clang-format")
 
+CLANG_FORMAT_VERSION = subprocess.check_output([CLANG_FORMAT_BIN, '--version'])
+
 COLUMN_LIMIT = 80
 for line in fmt.split("\n"):
     line = line.split(":")
@@ -135,6 +140,38 @@ def custom_format(filename):
     return out
 
 
+def hash_code_and_formatter(code):
+    hasher = hashlib.sha256()
+
+    hasher.update(code.encode())
+    hasher.update(CLANG_FORMAT_VERSION)
+    with open(__file__, 'rb') as f:
+        hasher.update(f.read())
+
+    return hasher.hexdigest()
+
+
+def custom_format_cached(filename):
+    filename_hash = hashlib.sha256(filename.encode()).hexdigest()
+    cache_file = os.path.join(FORMAT_CACHE_DIR, filename_hash)
+
+    if os.path.exists(cache_file):
+        with open(filename) as f:
+            code = f.read()
+        code_hash = hash_code_and_formatter(code)
+        with open(cache_file) as f:
+            if f.read() == code_hash:
+                return code
+
+    code = custom_format(filename)
+
+    code_hash = hash_code_and_formatter(code)
+    with open(cache_file, 'w') as f:
+        f.write(code_hash)
+
+    return code
+
+
 args = sys.argv[1:]
 if len(args) == 0:
     print("Usage: ./format.py [-i] <filename>")
@@ -150,7 +187,7 @@ if args[0] == "-i":
     args = args[1:]
 
 for filename in args:
-    code = custom_format(filename)
+    code = custom_format_cached(filename)
     if in_place:
         with open(filename, "w") as f:
             f.write(code)
diff --git a/.gitignore b/.gitignore
index bc06ef2d..4f25e5e4 100644
--- a/.gitignore
+++ b/.gitignore
@@ -7,6 +7,7 @@
 *.so
 *.swp
 .DS_Store
+.format-cache
 .sync_tmp
 .test
 .test2
@@ -113,4 +114,4 @@ utils/replay_record/persistent_demo_replay_argparse
 utils/plot_ui/afl-plot-ui
 vuln_prog
 argv_fuzz_demo
-argv_fuzz_persistent_demo
\ No newline at end of file
+argv_fuzz_persistent_demo
diff --git a/GNUmakefile b/GNUmakefile
index bbe95908..697c48af 100644
--- a/GNUmakefile
+++ b/GNUmakefile
@@ -684,6 +684,7 @@ deepclean:	clean
 	rm -rf unicorn_mode/unicornafl
 	rm -rf qemu_mode/qemuafl
 	rm -rf nyx_mode/libnyx nyx_mode/packer nyx_mode/QEMU-Nyx
+	rm -rf .format-cache
 ifeq "$(IN_REPO)" "1"
 	git checkout coresight_mode/coresight-trace
 	git checkout unicorn_mode/unicornafl