diff --git a/stdlib/builtins.pyi b/stdlib/builtins.pyi
index 2a8e3dc12f41..e88d9d8d27ae 100644
--- a/stdlib/builtins.pyi
+++ b/stdlib/builtins.pyi
@@ -335,16 +335,19 @@ class str(Sequence[str]):
     def capitalize(self) -> str: ...
     def casefold(self) -> str: ...
     def center(self, __width: int, __fillchar: str = ...) -> str: ...
-    def count(self, x: str, __start: Optional[int] = ..., __end: Optional[int] = ...) -> int: ...
+    def count(self, x: str, __start: Optional[_SupportsIndex] = ..., __end: Optional[_SupportsIndex] = ...) -> int: ...
     def encode(self, encoding: str = ..., errors: str = ...) -> bytes: ...
     def endswith(
-        self, __suffix: Union[str, Tuple[str, ...]], __start: Optional[int] = ..., __end: Optional[int] = ...
+        self,
+        __suffix: Union[str, Tuple[str, ...]],
+        __start: Optional[_SupportsIndex] = ...,
+        __end: Optional[_SupportsIndex] = ...,
     ) -> bool: ...
     def expandtabs(self, tabsize: int = ...) -> str: ...
-    def find(self, __sub: str, __start: Optional[int] = ..., __end: Optional[int] = ...) -> int: ...
+    def find(self, __sub: str, __start: Optional[_SupportsIndex] = ..., __end: Optional[_SupportsIndex] = ...) -> int: ...
     def format(self, *args: object, **kwargs: object) -> str: ...
     def format_map(self, map: _FormatMapMapping) -> str: ...
-    def index(self, __sub: str, __start: Optional[int] = ..., __end: Optional[int] = ...) -> int: ...
+    def index(self, __sub: str, __start: Optional[_SupportsIndex] = ..., __end: Optional[_SupportsIndex] = ...) -> int: ...
     def isalnum(self) -> bool: ...
     def isalpha(self) -> bool: ...
     if sys.version_info >= (3, 7):
@@ -367,8 +370,8 @@ class str(Sequence[str]):
     if sys.version_info >= (3, 9):
         def removeprefix(self, __prefix: str) -> str: ...
         def removesuffix(self, __suffix: str) -> str: ...
-    def rfind(self, __sub: str, __start: Optional[int] = ..., __end: Optional[int] = ...) -> int: ...
-    def rindex(self, __sub: str, __start: Optional[int] = ..., __end: Optional[int] = ...) -> int: ...
+    def rfind(self, __sub: str, __start: Optional[_SupportsIndex] = ..., __end: Optional[_SupportsIndex] = ...) -> int: ...
+    def rindex(self, __sub: str, __start: Optional[_SupportsIndex] = ..., __end: Optional[_SupportsIndex] = ...) -> int: ...
     def rjust(self, __width: int, __fillchar: str = ...) -> str: ...
     def rpartition(self, __sep: str) -> Tuple[str, str, str]: ...
     def rsplit(self, sep: Optional[str] = ..., maxsplit: int = ...) -> List[str]: ...
@@ -376,7 +379,10 @@ class str(Sequence[str]):
     def split(self, sep: Optional[str] = ..., maxsplit: int = ...) -> List[str]: ...
     def splitlines(self, keepends: bool = ...) -> List[str]: ...
     def startswith(
-        self, __prefix: Union[str, Tuple[str, ...]], __start: Optional[int] = ..., __end: Optional[int] = ...
+        self,
+        __prefix: Union[str, Tuple[str, ...]],
+        __start: Optional[_SupportsIndex] = ...,
+        __end: Optional[_SupportsIndex] = ...,
     ) -> bool: ...
     def strip(self, __chars: Optional[str] = ...) -> str: ...
     def swapcase(self) -> str: ...
@@ -423,18 +429,27 @@ class bytes(ByteString):
     def __new__(cls: Type[_T], o: SupportsBytes) -> _T: ...
     def capitalize(self) -> bytes: ...
     def center(self, __width: int, __fillchar: bytes = ...) -> bytes: ...
-    def count(self, __sub: Union[bytes, int], __start: Optional[int] = ..., __end: Optional[int] = ...) -> int: ...
+    def count(
+        self, __sub: Union[bytes, int], __start: Optional[_SupportsIndex] = ..., __end: Optional[_SupportsIndex] = ...
+    ) -> int: ...
     def decode(self, encoding: str = ..., errors: str = ...) -> str: ...
     def endswith(
-        self, __suffix: Union[bytes, Tuple[bytes, ...]], __start: Optional[int] = ..., __end: Optional[int] = ...
+        self,
+        __suffix: Union[bytes, Tuple[bytes, ...]],
+        __start: Optional[_SupportsIndex] = ...,
+        __end: Optional[_SupportsIndex] = ...,
     ) -> bool: ...
     def expandtabs(self, tabsize: int = ...) -> bytes: ...
-    def find(self, __sub: Union[bytes, int], __start: Optional[int] = ..., __end: Optional[int] = ...) -> int: ...
+    def find(
+        self, __sub: Union[bytes, int], __start: Optional[_SupportsIndex] = ..., __end: Optional[_SupportsIndex] = ...
+    ) -> int: ...
     if sys.version_info >= (3, 8):
         def hex(self, sep: Union[str, bytes] = ..., bytes_per_sep: int = ...) -> str: ...
     else:
         def hex(self) -> str: ...
-    def index(self, __sub: Union[bytes, int], __start: Optional[int] = ..., __end: Optional[int] = ...) -> int: ...
+    def index(
+        self, __sub: Union[bytes, int], __start: Optional[_SupportsIndex] = ..., __end: Optional[_SupportsIndex] = ...
+    ) -> int: ...
     def isalnum(self) -> bool: ...
     def isalpha(self) -> bool: ...
     if sys.version_info >= (3, 7):
@@ -453,8 +468,12 @@ class bytes(ByteString):
     if sys.version_info >= (3, 9):
         def removeprefix(self, __prefix: bytes) -> bytes: ...
         def removesuffix(self, __suffix: bytes) -> bytes: ...
-    def rfind(self, __sub: Union[bytes, int], __start: Optional[int] = ..., __end: Optional[int] = ...) -> int: ...
-    def rindex(self, __sub: Union[bytes, int], __start: Optional[int] = ..., __end: Optional[int] = ...) -> int: ...
+    def rfind(
+        self, __sub: Union[bytes, int], __start: Optional[_SupportsIndex] = ..., __end: Optional[_SupportsIndex] = ...
+    ) -> int: ...
+    def rindex(
+        self, __sub: Union[bytes, int], __start: Optional[_SupportsIndex] = ..., __end: Optional[_SupportsIndex] = ...
+    ) -> int: ...
     def rjust(self, __width: int, __fillchar: bytes = ...) -> bytes: ...
     def rpartition(self, __sep: bytes) -> Tuple[bytes, bytes, bytes]: ...
     def rsplit(self, sep: Optional[bytes] = ..., maxsplit: int = ...) -> List[bytes]: ...
@@ -462,7 +481,10 @@ class bytes(ByteString):
     def split(self, sep: Optional[bytes] = ..., maxsplit: int = ...) -> List[bytes]: ...
     def splitlines(self, keepends: bool = ...) -> List[bytes]: ...
     def startswith(
-        self, __prefix: Union[bytes, Tuple[bytes, ...]], __start: Optional[int] = ..., __end: Optional[int] = ...
+        self,
+        __prefix: Union[bytes, Tuple[bytes, ...]],
+        __start: Optional[_SupportsIndex] = ...,
+        __end: Optional[_SupportsIndex] = ...,
     ) -> bool: ...
     def strip(self, __bytes: Optional[bytes] = ...) -> bytes: ...
     def swapcase(self) -> bytes: ...
@@ -509,20 +531,29 @@ class bytearray(MutableSequence[int], ByteString):
     def append(self, __item: int) -> None: ...
     def capitalize(self) -> bytearray: ...
     def center(self, __width: int, __fillchar: bytes = ...) -> bytearray: ...
-    def count(self, __sub: Union[bytes, int], __start: Optional[int] = ..., __end: Optional[int] = ...) -> int: ...
+    def count(
+        self, __sub: Union[bytes, int], __start: Optional[_SupportsIndex] = ..., __end: Optional[_SupportsIndex] = ...
+    ) -> int: ...
     def copy(self) -> bytearray: ...
     def decode(self, encoding: str = ..., errors: str = ...) -> str: ...
     def endswith(
-        self, __suffix: Union[bytes, Tuple[bytes, ...]], __start: Optional[int] = ..., __end: Optional[int] = ...
+        self,
+        __suffix: Union[bytes, Tuple[bytes, ...]],
+        __start: Optional[_SupportsIndex] = ...,
+        __end: Optional[_SupportsIndex] = ...,
     ) -> bool: ...
     def expandtabs(self, tabsize: int = ...) -> bytearray: ...
     def extend(self, __iterable_of_ints: Iterable[int]) -> None: ...
-    def find(self, __sub: Union[bytes, int], __start: Optional[int] = ..., __end: Optional[int] = ...) -> int: ...
+    def find(
+        self, __sub: Union[bytes, int], __start: Optional[_SupportsIndex] = ..., __end: Optional[_SupportsIndex] = ...
+    ) -> int: ...
     if sys.version_info >= (3, 8):
         def hex(self, sep: Union[str, bytes] = ..., bytes_per_sep: int = ...) -> str: ...
     else:
         def hex(self) -> str: ...
-    def index(self, __sub: Union[bytes, int], __start: Optional[int] = ..., __end: Optional[int] = ...) -> int: ...
+    def index(
+        self, __sub: Union[bytes, int], __start: Optional[_SupportsIndex] = ..., __end: Optional[_SupportsIndex] = ...
+    ) -> int: ...
     def insert(self, __index: int, __item: int) -> None: ...
     def isalnum(self) -> bool: ...
     def isalpha(self) -> bool: ...
@@ -542,8 +573,12 @@ class bytearray(MutableSequence[int], ByteString):
         def removeprefix(self, __prefix: bytes) -> bytearray: ...
         def removesuffix(self, __suffix: bytes) -> bytearray: ...
     def replace(self, __old: bytes, __new: bytes, __count: int = ...) -> bytearray: ...
-    def rfind(self, __sub: Union[bytes, int], __start: Optional[int] = ..., __end: Optional[int] = ...) -> int: ...
-    def rindex(self, __sub: Union[bytes, int], __start: Optional[int] = ..., __end: Optional[int] = ...) -> int: ...
+    def rfind(
+        self, __sub: Union[bytes, int], __start: Optional[_SupportsIndex] = ..., __end: Optional[_SupportsIndex] = ...
+    ) -> int: ...
+    def rindex(
+        self, __sub: Union[bytes, int], __start: Optional[_SupportsIndex] = ..., __end: Optional[_SupportsIndex] = ...
+    ) -> int: ...
     def rjust(self, __width: int, __fillchar: bytes = ...) -> bytearray: ...
     def rpartition(self, __sep: bytes) -> Tuple[bytearray, bytearray, bytearray]: ...
     def rsplit(self, sep: Optional[bytes] = ..., maxsplit: int = ...) -> List[bytearray]: ...
@@ -551,7 +586,10 @@ class bytearray(MutableSequence[int], ByteString):
     def split(self, sep: Optional[bytes] = ..., maxsplit: int = ...) -> List[bytearray]: ...
     def splitlines(self, keepends: bool = ...) -> List[bytearray]: ...
     def startswith(
-        self, __prefix: Union[bytes, Tuple[bytes, ...]], __start: Optional[int] = ..., __end: Optional[int] = ...
+        self,
+        __prefix: Union[bytes, Tuple[bytes, ...]],
+        __start: Optional[_SupportsIndex] = ...,
+        __end: Optional[_SupportsIndex] = ...,
     ) -> bool: ...
     def strip(self, __bytes: Optional[bytes] = ...) -> bytearray: ...
     def swapcase(self) -> bytearray: ...