diff --git a/tools/getsharedopensslhasquic.py b/tools/getsharedopensslhasquic.py
index a0ad809db21..f4349285e2f 100644
--- a/tools/getsharedopensslhasquic.py
+++ b/tools/getsharedopensslhasquic.py
@@ -14,7 +14,7 @@ def get_has_quic(include_path):
     except OSError:
       return False
 
-    regex = '^#\s*define OPENSSL_INFO_QUIC'
+    regex = r'^#\s*define OPENSSL_INFO_QUIC'
 
     for line in f:
       if (re.match(regex, line)):
diff --git a/tools/js2c.py b/tools/js2c.py
index b8b26efc882..504345e7894 100755
--- a/tools/js2c.py
+++ b/tools/js2c.py
@@ -92,7 +92,7 @@ INITIALIZER = '{{"{0}", UnionBytes{{{1}, {2}}} }},'
 
 CONFIG_GYPI_ID = 'config_raw'
 
-SLUGGER_RE =re.compile('[.\-/]')
+SLUGGER_RE = re.compile(r'[.\-/]')
 
 is_verbose = False
 
diff --git a/tools/v8_gypfiles/GN-scraper.py b/tools/v8_gypfiles/GN-scraper.py
index ec72f1d47ea..1c9f2a7c4b2 100644
--- a/tools/v8_gypfiles/GN-scraper.py
+++ b/tools/v8_gypfiles/GN-scraper.py
@@ -3,7 +3,7 @@
 import re
 import os
 
-PLAIN_SOURCE_RE = re.compile('\s*"([^/$].+)"\s*')
+PLAIN_SOURCE_RE = re.compile(r'\s*"([^/$].+)"\s*')
 def DoMain(args):
   gn_filename, pattern = args
   src_root = os.path.dirname(gn_filename)