diff --git a/tools/cef_api_hash.py b/tools/cef_api_hash.py
index 39eefa075..d2de455c0 100644
--- a/tools/cef_api_hash.py
+++ b/tools/cef_api_hash.py
@@ -133,11 +133,11 @@ class cef_api_hash:
   def __parse_objects(self, content):
     """ Returns array of objects in content file. """
     objects = []
-    content = re.sub("//.*\n", "", content)
+    content = re.sub(r"//.*\n", "", content)
 
     # function declarations
     for m in re.finditer(
-        "\nCEF_EXPORT\s+?.*?\s+?(\w+)\s*?\(.*?\)\s*?;",
+        r"\nCEF_EXPORT\s+?.*?\s+?(\w+)\s*?\(.*?\)\s*?;",
         content,
         flags=re.DOTALL):
       object = {"name": m.group(1), "text": m.group(0).strip()}
@@ -145,7 +145,7 @@ class cef_api_hash:
 
     # structs
     for m in re.finditer(
-        "\ntypedef\s+?struct\s+?(\w+)\s+?\{.*?\}\s+?(\w+)\s*?;",
+        r"\ntypedef\s+?struct\s+?(\w+)\s+?\{.*?\}\s+?(\w+)\s*?;",
         content,
         flags=re.DOTALL):
       object = {"name": m.group(2), "text": m.group(0).strip()}
@@ -153,12 +153,12 @@ class cef_api_hash:
 
     # enums
     for m in re.finditer(
-        "\ntypedef\s+?enum\s+?\{.*?\}\s+?(\w+)\s*?;", content, flags=re.DOTALL):
+        r"\ntypedef\s+?enum\s+?\{.*?\}\s+?(\w+)\s*?;", content, flags=re.DOTALL):
       object = {"name": m.group(1), "text": m.group(0).strip()}
       objects.append(object)
 
     # typedefs
-    for m in re.finditer("\ntypedef\s+?.*?\s+(\w+);", content, flags=0):
+    for m in re.finditer(r"\ntypedef\s+?.*?\s+(\w+);", content, flags=0):
       object = {"name": m.group(1), "text": m.group(0).strip()}
       objects.append(object)
 
@@ -168,7 +168,7 @@ class cef_api_hash:
     """ Grab defined CEF_STRING_TYPE_xxx """
     objects = []
     for m in re.finditer(
-        "\n\s*?#\s*?define\s+?(CEF_STRING_TYPE_\w+)\s+?.*?\n", content,
+        r"\n\s*?#\s*?define\s+?(CEF_STRING_TYPE_\w+)\s+?.*?\n", content,
         flags=0):
       object = {
           "name": m.group(1),
@@ -179,8 +179,8 @@ class cef_api_hash:
 
   def __prepare_text(self, text):
     text = text.strip()
-    text = re.sub("\s+", " ", text)
-    text = re.sub("\(\s+", "(", text)
+    text = re.sub(r"\s+", " ", text)
+    text = re.sub(r"\(\s+", "(", text)
     return text
 
   def __get_final_sig(self, objects, platform):
diff --git a/tools/cef_parser.py b/tools/cef_parser.py
index 6a7181dad..1cc0fb059 100644
--- a/tools/cef_parser.py
+++ b/tools/cef_parser.py
@@ -273,7 +273,7 @@ def format_translation_includes(header, body):
     result += '#include "libcef_dll/template_util.h"\n'
 
   # identify what CppToC classes are being used
-  p = re.compile('([A-Za-z0-9_]{1,})CppToC')
+  p = re.compile(r'([A-Za-z0-9_]{1,})CppToC')
   list = sorted(set(p.findall(body)))
   for item in list:
     directory = ''
@@ -286,7 +286,7 @@ def format_translation_includes(header, body):
               get_capi_name(item[3:], False)+'_cpptoc.h"\n'
 
   # identify what CToCpp classes are being used
-  p = re.compile('([A-Za-z0-9_]{1,})CToCpp')
+  p = re.compile(r'([A-Za-z0-9_]{1,})CToCpp')
   list = sorted(set(p.findall(body)))
   for item in list:
     directory = ''
@@ -355,21 +355,21 @@ def dict_to_str(dict):
 
 
 # regex for matching comment-formatted attributes
-_cre_attrib = '/\*--cef\(([A-Za-z0-9_ ,=:\n]{0,})\)--\*/'
+_cre_attrib = r'/\*--cef\(([A-Za-z0-9_ ,=:\n]{0,})\)--\*/'
 # regex for matching class and function names
-_cre_cfname = '([A-Za-z0-9_]{1,})'
+_cre_cfname = r'([A-Za-z0-9_]{1,})'
 # regex for matching class and function names including path separators
-_cre_cfnameorpath = '([A-Za-z0-9_\/]{1,})'
+_cre_cfnameorpath = r'([A-Za-z0-9_\/]{1,})'
 # regex for matching typedef value and name combination
-_cre_typedef = '([A-Za-z0-9_<>:,\*\&\s]{1,})'
+_cre_typedef = r'([A-Za-z0-9_<>:,\*\&\s]{1,})'
 # regex for matching function return value and name combination
-_cre_func = '([A-Za-z][A-Za-z0-9_<>:,\*\&\s]{1,})'
+_cre_func = r'([A-Za-z][A-Za-z0-9_<>:,\*\&\s]{1,})'
 # regex for matching virtual function modifiers + arbitrary whitespace
-_cre_vfmod = '([\sA-Za-z0-9_]{0,})'
+_cre_vfmod = r'([\sA-Za-z0-9_]{0,})'
 # regex for matching arbitrary whitespace
-_cre_space = '[\s]{1,}'
+_cre_space = r'[\s]{1,}'
 # regex for matching optional virtual keyword
-_cre_virtual = '(?:[\s]{1,}virtual){0,1}'
+_cre_virtual = r'(?:[\s]{1,}virtual){0,1}'
 
 # Simple translation types. Format is:
 #   'cpp_type' : ['capi_type', 'capi_default_value']
@@ -437,11 +437,11 @@ def get_function_impls(content, ident, has_impl=True):
   content = content.replace('NO_SANITIZE("cfi-icall")\n', '')
 
   # extract the functions
-  find_regex = '\n' + _cre_func + '\((.*?)\)([A-Za-z0-9_\s]{0,})'
+  find_regex = r'\n' + _cre_func + r'\((.*?)\)([A-Za-z0-9_\s]{0,})'
   if has_impl:
-    find_regex += '\{(.*?)\n\}'
+    find_regex += r'\{(.*?)\n\}'
   else:
-    find_regex += '(;)'
+    find_regex += r'(;)'
   p = re.compile(find_regex, re.MULTILINE | re.DOTALL)
   list = p.findall(content)
 
@@ -603,7 +603,7 @@ class obj_header:
     data = data.replace("> >", ">>")
 
     # extract global typedefs
-    p = re.compile('\ntypedef' + _cre_space + _cre_typedef + ';',
+    p = re.compile(r'\ntypedef' + _cre_space + _cre_typedef + r';',
                    re.MULTILINE | re.DOTALL)
     list = p.findall(data)
     if len(list) > 0:
@@ -617,7 +617,7 @@ class obj_header:
         self.typedefs.append(obj_typedef(self, filename, value, alias))
 
     # extract global functions
-    p = re.compile('\n' + _cre_attrib + '\n' + _cre_func + '\((.*?)\)',
+    p = re.compile(r'\n' + _cre_attrib + r'\n' + _cre_func + r'\((.*?)\)',
                    re.MULTILINE | re.DOTALL)
     list = p.findall(data)
     if len(list) > 0:
@@ -631,17 +631,17 @@ class obj_header:
             obj_function(self, filename, attrib, retval, argval, comment))
 
     # extract includes
-    p = re.compile('\n#include \"include/' + _cre_cfnameorpath + '.h')
+    p = re.compile(r'\n#include \"include/' + _cre_cfnameorpath + r'.h')
     includes = p.findall(data)
 
     # extract forward declarations
-    p = re.compile('\nclass' + _cre_space + _cre_cfname + ';')
+    p = re.compile(r'\nclass' + _cre_space + _cre_cfname + r';')
     forward_declares = p.findall(data)
 
     # extract empty classes
-    p = re.compile('\n' + _cre_attrib + '\nclass' + _cre_space + _cre_cfname +
-                   _cre_space + ':' + _cre_space + 'public' + _cre_virtual +
-                   _cre_space + _cre_cfname + _cre_space + '{};',
+    p = re.compile(r'\n' + _cre_attrib + r'\nclass' + _cre_space + _cre_cfname +
+                   _cre_space + r':' + _cre_space + r'public' + _cre_virtual +
+                   _cre_space + _cre_cfname + _cre_space + r'{};',
                    re.MULTILINE | re.DOTALL)
     list = p.findall(data)
     if len(list) > 0:
@@ -663,9 +663,9 @@ class obj_header:
       data = p.sub('', data)
 
     # extract classes
-    p = re.compile('\n' + _cre_attrib + '\nclass' + _cre_space + _cre_cfname +
-                   _cre_space + ':' + _cre_space + 'public' + _cre_virtual +
-                   _cre_space + _cre_cfname + _cre_space + '{(.*?)\n};',
+    p = re.compile(r'\n' + _cre_attrib + r'\nclass' + _cre_space + _cre_cfname +
+                   _cre_space + r':' + _cre_space + r'public' + _cre_virtual +
+                   _cre_space + _cre_cfname + _cre_space + r'{(.*?)\n};',
                    re.MULTILINE | re.DOTALL)
     list = p.findall(data)
     if len(list) > 0:
@@ -852,7 +852,7 @@ class obj_class:
 
     # extract typedefs
     p = re.compile(
-        '\n' + _cre_space + 'typedef' + _cre_space + _cre_typedef + ';',
+        r'\n' + _cre_space + r'typedef' + _cre_space + _cre_typedef + r';',
         re.MULTILINE | re.DOTALL)
     list = p.findall(body)
 
@@ -867,8 +867,8 @@ class obj_class:
       self.typedefs.append(obj_typedef(self, filename, value, alias))
 
     # extract static functions
-    p = re.compile('\n' + _cre_space + _cre_attrib + '\n' + _cre_space +
-                   'static' + _cre_space + _cre_func + '\((.*?)\)',
+    p = re.compile(r'\n' + _cre_space + _cre_attrib + r'\n' + _cre_space +
+                   r'static' + _cre_space + _cre_func + r'\((.*?)\)',
                    re.MULTILINE | re.DOTALL)
     list = p.findall(body)
 
@@ -882,8 +882,8 @@ class obj_class:
 
     # extract virtual functions
     p = re.compile(
-        '\n' + _cre_space + _cre_attrib + '\n' + _cre_space + 'virtual' +
-        _cre_space + _cre_func + '\((.*?)\)' + _cre_vfmod,
+        r'\n' + _cre_space + _cre_attrib + r'\n' + _cre_space + r'virtual' +
+        _cre_space + _cre_func + r'\((.*?)\)' + _cre_vfmod,
         re.MULTILINE | re.DOTALL)
     list = p.findall(body)
 
@@ -1766,7 +1766,7 @@ class obj_analysis:
       return {'result_type': 'structure', 'result_value': value}
 
     # check for CEF reference pointers
-    p = re.compile('^CefRefPtr<(.*?)>$', re.DOTALL)
+    p = re.compile(r'^CefRefPtr<(.*?)>$', re.DOTALL)
     list = p.findall(value)
     if len(list) == 1:
       return {
@@ -1776,7 +1776,7 @@ class obj_analysis:
       }
 
     # check for CEF owned pointers
-    p = re.compile('^CefOwnPtr<(.*?)>$', re.DOTALL)
+    p = re.compile(r'^CefOwnPtr<(.*?)>$', re.DOTALL)
     list = p.findall(value)
     if len(list) == 1:
       return {
@@ -1786,7 +1786,7 @@ class obj_analysis:
       }
 
     # check for CEF raw pointers
-    p = re.compile('^CefRawPtr<(.*?)>$', re.DOTALL)
+    p = re.compile(r'^CefRawPtr<(.*?)>$', re.DOTALL)
     list = p.findall(value)
     if len(list) == 1:
       return {
diff --git a/tools/make_pack_header.py b/tools/make_pack_header.py
index 1afe8d069..a04b3ea45 100644
--- a/tools/make_pack_header.py
+++ b/tools/make_pack_header.py
@@ -34,10 +34,10 @@ def MakeFileSegment(input, all_names):
   #   #define IDR_RESOURCE_NAME 12345
   # [1] See https://crbug.com/684788#c18
 
-  regex = '#define\s([A-Za-z0-9_]{1,})\s+'
+  regex = r'#define\s([A-Za-z0-9_]{1,})\s+'
   if contents.find('ui::WhitelistedResource') > 0:
-    regex += '.*<'
-  regex += '([0-9]{1,})'
+    regex += r'.*<'
+  regex += r'([0-9]{1,})'
 
   # identify the defines in the file
   p = re.compile(regex)