diff --git a/homeassistant/components/history/__init__.py b/homeassistant/components/history/__init__.py
index 27acff54f99..77301532d3d 100644
--- a/homeassistant/components/history/__init__.py
+++ b/homeassistant/components/history/__init__.py
@@ -24,10 +24,10 @@ from homeassistant.components.recorder.statistics import (
 )
 from homeassistant.components.recorder.util import session_scope
 from homeassistant.components.websocket_api import messages
-from homeassistant.components.websocket_api.const import JSON_DUMP
 from homeassistant.core import HomeAssistant
 import homeassistant.helpers.config_validation as cv
 from homeassistant.helpers.entityfilter import INCLUDE_EXCLUDE_BASE_FILTER_SCHEMA
+from homeassistant.helpers.json import JSON_DUMP
 from homeassistant.helpers.typing import ConfigType
 import homeassistant.util.dt as dt_util
 
diff --git a/homeassistant/components/logbook/websocket_api.py b/homeassistant/components/logbook/websocket_api.py
index 0bb7877b95b..7265bcbae86 100644
--- a/homeassistant/components/logbook/websocket_api.py
+++ b/homeassistant/components/logbook/websocket_api.py
@@ -14,9 +14,9 @@ from homeassistant.components import websocket_api
 from homeassistant.components.recorder import get_instance
 from homeassistant.components.websocket_api import messages
 from homeassistant.components.websocket_api.connection import ActiveConnection
-from homeassistant.components.websocket_api.const import JSON_DUMP
 from homeassistant.core import CALLBACK_TYPE, Event, HomeAssistant, callback
 from homeassistant.helpers.event import async_track_point_in_utc_time
+from homeassistant.helpers.json import JSON_DUMP
 import homeassistant.util.dt as dt_util
 
 from .helpers import (
diff --git a/homeassistant/components/recorder/const.py b/homeassistant/components/recorder/const.py
index e558d19b530..e94092d2154 100644
--- a/homeassistant/components/recorder/const.py
+++ b/homeassistant/components/recorder/const.py
@@ -1,12 +1,11 @@
 """Recorder constants."""
 
-from functools import partial
-import json
-from typing import Final
 
 from homeassistant.backports.enum import StrEnum
 from homeassistant.const import ATTR_ATTRIBUTION, ATTR_RESTORED, ATTR_SUPPORTED_FEATURES
-from homeassistant.helpers.json import JSONEncoder
+from homeassistant.helpers.json import (  # noqa: F401 pylint: disable=unused-import
+    JSON_DUMP,
+)
 
 DATA_INSTANCE = "recorder_instance"
 SQLITE_URL_PREFIX = "sqlite://"
@@ -27,7 +26,6 @@ MAX_ROWS_TO_PURGE = 998
 
 DB_WORKER_PREFIX = "DbWorker"
 
-JSON_DUMP: Final = partial(json.dumps, cls=JSONEncoder, separators=(",", ":"))
 
 ALL_DOMAIN_EXCLUDE_ATTRS = {ATTR_ATTRIBUTION, ATTR_RESTORED, ATTR_SUPPORTED_FEATURES}
 
diff --git a/homeassistant/components/recorder/core.py b/homeassistant/components/recorder/core.py
index 7df4cf57e56..8b15e15042f 100644
--- a/homeassistant/components/recorder/core.py
+++ b/homeassistant/components/recorder/core.py
@@ -744,11 +744,12 @@ class Recorder(threading.Thread):
             return
 
         try:
-            shared_data = EventData.shared_data_from_event(event)
+            shared_data_bytes = EventData.shared_data_bytes_from_event(event)
         except (TypeError, ValueError) as ex:
             _LOGGER.warning("Event is not JSON serializable: %s: %s", event, ex)
             return
 
+        shared_data = shared_data_bytes.decode("utf-8")
         # Matching attributes found in the pending commit
         if pending_event_data := self._pending_event_data.get(shared_data):
             dbevent.event_data_rel = pending_event_data
@@ -756,7 +757,7 @@ class Recorder(threading.Thread):
         elif data_id := self._event_data_ids.get(shared_data):
             dbevent.data_id = data_id
         else:
-            data_hash = EventData.hash_shared_data(shared_data)
+            data_hash = EventData.hash_shared_data_bytes(shared_data_bytes)
             # Matching attributes found in the database
             if data_id := self._find_shared_data_in_db(data_hash, shared_data):
                 self._event_data_ids[shared_data] = dbevent.data_id = data_id
@@ -775,7 +776,7 @@ class Recorder(threading.Thread):
         assert self.event_session is not None
         try:
             dbstate = States.from_event(event)
-            shared_attrs = StateAttributes.shared_attrs_from_event(
+            shared_attrs_bytes = StateAttributes.shared_attrs_bytes_from_event(
                 event, self._exclude_attributes_by_domain
             )
         except (TypeError, ValueError) as ex:
@@ -786,6 +787,7 @@ class Recorder(threading.Thread):
             )
             return
 
+        shared_attrs = shared_attrs_bytes.decode("utf-8")
         dbstate.attributes = None
         # Matching attributes found in the pending commit
         if pending_attributes := self._pending_state_attributes.get(shared_attrs):
@@ -794,7 +796,7 @@ class Recorder(threading.Thread):
         elif attributes_id := self._state_attributes_ids.get(shared_attrs):
             dbstate.attributes_id = attributes_id
         else:
-            attr_hash = StateAttributes.hash_shared_attrs(shared_attrs)
+            attr_hash = StateAttributes.hash_shared_attrs_bytes(shared_attrs_bytes)
             # Matching attributes found in the database
             if attributes_id := self._find_shared_attr_in_db(attr_hash, shared_attrs):
                 dbstate.attributes_id = attributes_id
diff --git a/homeassistant/components/recorder/models.py b/homeassistant/components/recorder/models.py
index 70c816c2af5..e0a22184cc8 100644
--- a/homeassistant/components/recorder/models.py
+++ b/homeassistant/components/recorder/models.py
@@ -3,12 +3,12 @@ from __future__ import annotations
 
 from collections.abc import Callable
 from datetime import datetime, timedelta
-import json
 import logging
 from typing import Any, TypedDict, cast, overload
 
 import ciso8601
 from fnvhash import fnv1a_32
+import orjson
 from sqlalchemy import (
     JSON,
     BigInteger,
@@ -46,9 +46,10 @@ from homeassistant.const import (
     MAX_LENGTH_STATE_STATE,
 )
 from homeassistant.core import Context, Event, EventOrigin, State, split_entity_id
+from homeassistant.helpers.json import JSON_DUMP, json_bytes
 import homeassistant.util.dt as dt_util
 
-from .const import ALL_DOMAIN_EXCLUDE_ATTRS, JSON_DUMP
+from .const import ALL_DOMAIN_EXCLUDE_ATTRS
 
 # SQLAlchemy Schema
 # pylint: disable=invalid-name
@@ -132,7 +133,7 @@ class JSONLiteral(JSON):  # type: ignore[misc]
 
         def process(value: Any) -> str:
             """Dump json."""
-            return json.dumps(value)
+            return JSON_DUMP(value)
 
         return process
 
@@ -199,7 +200,7 @@ class Events(Base):  # type: ignore[misc,valid-type]
         try:
             return Event(
                 self.event_type,
-                json.loads(self.event_data) if self.event_data else {},
+                orjson.loads(self.event_data) if self.event_data else {},
                 EventOrigin(self.origin)
                 if self.origin
                 else EVENT_ORIGIN_ORDER[self.origin_idx],
@@ -207,7 +208,7 @@ class Events(Base):  # type: ignore[misc,valid-type]
                 context=context,
             )
         except ValueError:
-            # When json.loads fails
+            # When orjson.loads fails
             _LOGGER.exception("Error converting to event: %s", self)
             return None
 
@@ -235,25 +236,26 @@ class EventData(Base):  # type: ignore[misc,valid-type]
     @staticmethod
     def from_event(event: Event) -> EventData:
         """Create object from an event."""
-        shared_data = JSON_DUMP(event.data)
+        shared_data = json_bytes(event.data)
         return EventData(
-            shared_data=shared_data, hash=EventData.hash_shared_data(shared_data)
+            shared_data=shared_data.decode("utf-8"),
+            hash=EventData.hash_shared_data_bytes(shared_data),
         )
 
     @staticmethod
-    def shared_data_from_event(event: Event) -> str:
-        """Create shared_attrs from an event."""
-        return JSON_DUMP(event.data)
+    def shared_data_bytes_from_event(event: Event) -> bytes:
+        """Create shared_data from an event."""
+        return json_bytes(event.data)
 
     @staticmethod
-    def hash_shared_data(shared_data: str) -> int:
+    def hash_shared_data_bytes(shared_data_bytes: bytes) -> int:
         """Return the hash of json encoded shared data."""
-        return cast(int, fnv1a_32(shared_data.encode("utf-8")))
+        return cast(int, fnv1a_32(shared_data_bytes))
 
     def to_native(self) -> dict[str, Any]:
         """Convert to an HA state object."""
         try:
-            return cast(dict[str, Any], json.loads(self.shared_data))
+            return cast(dict[str, Any], orjson.loads(self.shared_data))
         except ValueError:
             _LOGGER.exception("Error converting row to event data: %s", self)
             return {}
@@ -340,9 +342,9 @@ class States(Base):  # type: ignore[misc,valid-type]
             parent_id=self.context_parent_id,
         )
         try:
-            attrs = json.loads(self.attributes) if self.attributes else {}
+            attrs = orjson.loads(self.attributes) if self.attributes else {}
         except ValueError:
-            # When json.loads fails
+            # When orjson.loads fails
             _LOGGER.exception("Error converting row to state: %s", self)
             return None
         if self.last_changed is None or self.last_changed == self.last_updated:
@@ -388,40 +390,39 @@ class StateAttributes(Base):  # type: ignore[misc,valid-type]
         """Create object from a state_changed event."""
         state: State | None = event.data.get("new_state")
         # None state means the state was removed from the state machine
-        dbstate = StateAttributes(
-            shared_attrs="{}" if state is None else JSON_DUMP(state.attributes)
-        )
-        dbstate.hash = StateAttributes.hash_shared_attrs(dbstate.shared_attrs)
+        attr_bytes = b"{}" if state is None else json_bytes(state.attributes)
+        dbstate = StateAttributes(shared_attrs=attr_bytes.decode("utf-8"))
+        dbstate.hash = StateAttributes.hash_shared_attrs_bytes(attr_bytes)
         return dbstate
 
     @staticmethod
-    def shared_attrs_from_event(
+    def shared_attrs_bytes_from_event(
         event: Event, exclude_attrs_by_domain: dict[str, set[str]]
-    ) -> str:
+    ) -> bytes:
         """Create shared_attrs from a state_changed event."""
         state: State | None = event.data.get("new_state")
         # None state means the state was removed from the state machine
         if state is None:
-            return "{}"
+            return b"{}"
         domain = split_entity_id(state.entity_id)[0]
         exclude_attrs = (
             exclude_attrs_by_domain.get(domain, set()) | ALL_DOMAIN_EXCLUDE_ATTRS
         )
-        return JSON_DUMP(
+        return json_bytes(
             {k: v for k, v in state.attributes.items() if k not in exclude_attrs}
         )
 
     @staticmethod
-    def hash_shared_attrs(shared_attrs: str) -> int:
-        """Return the hash of json encoded shared attributes."""
-        return cast(int, fnv1a_32(shared_attrs.encode("utf-8")))
+    def hash_shared_attrs_bytes(shared_attrs_bytes: bytes) -> int:
+        """Return the hash of orjson encoded shared attributes."""
+        return cast(int, fnv1a_32(shared_attrs_bytes))
 
     def to_native(self) -> dict[str, Any]:
         """Convert to an HA state object."""
         try:
-            return cast(dict[str, Any], json.loads(self.shared_attrs))
+            return cast(dict[str, Any], orjson.loads(self.shared_attrs))
         except ValueError:
-            # When json.loads fails
+            # When orjson.loads fails
             _LOGGER.exception("Error converting row to state attributes: %s", self)
             return {}
 
@@ -835,7 +836,7 @@ def decode_attributes_from_row(
     if not source or source == EMPTY_JSON_OBJECT:
         return {}
     try:
-        attr_cache[source] = attributes = json.loads(source)
+        attr_cache[source] = attributes = orjson.loads(source)
     except ValueError:
         _LOGGER.exception("Error converting row to state attributes: %s", source)
         attr_cache[source] = attributes = {}
diff --git a/homeassistant/components/websocket_api/commands.py b/homeassistant/components/websocket_api/commands.py
index 61bcb8badf0..bea08722eb0 100644
--- a/homeassistant/components/websocket_api/commands.py
+++ b/homeassistant/components/websocket_api/commands.py
@@ -29,7 +29,7 @@ from homeassistant.helpers.event import (
     TrackTemplateResult,
     async_track_template_result,
 )
-from homeassistant.helpers.json import ExtendedJSONEncoder
+from homeassistant.helpers.json import JSON_DUMP, ExtendedJSONEncoder
 from homeassistant.helpers.service import async_get_all_descriptions
 from homeassistant.loader import IntegrationNotFound, async_get_integration
 from homeassistant.setup import DATA_SETUP_TIME, async_get_loaded_integrations
@@ -241,13 +241,13 @@ def handle_get_states(
     # to succeed for the UI to show.
     response = messages.result_message(msg["id"], states)
     try:
-        connection.send_message(const.JSON_DUMP(response))
+        connection.send_message(JSON_DUMP(response))
         return
     except (ValueError, TypeError):
         connection.logger.error(
             "Unable to serialize to JSON. Bad data found at %s",
             format_unserializable_data(
-                find_paths_unserializable_data(response, dump=const.JSON_DUMP)
+                find_paths_unserializable_data(response, dump=JSON_DUMP)
             ),
         )
     del response
@@ -256,13 +256,13 @@ def handle_get_states(
     serialized = []
     for state in states:
         try:
-            serialized.append(const.JSON_DUMP(state))
+            serialized.append(JSON_DUMP(state))
         except (ValueError, TypeError):
             # Error is already logged above
             pass
 
     # We now have partially serialized states. Craft some JSON.
-    response2 = const.JSON_DUMP(messages.result_message(msg["id"], ["TO_REPLACE"]))
+    response2 = JSON_DUMP(messages.result_message(msg["id"], ["TO_REPLACE"]))
     response2 = response2.replace('"TO_REPLACE"', ", ".join(serialized))
     connection.send_message(response2)
 
@@ -315,13 +315,13 @@ def handle_subscribe_entities(
     # to succeed for the UI to show.
     response = messages.event_message(msg["id"], data)
     try:
-        connection.send_message(const.JSON_DUMP(response))
+        connection.send_message(JSON_DUMP(response))
         return
     except (ValueError, TypeError):
         connection.logger.error(
             "Unable to serialize to JSON. Bad data found at %s",
             format_unserializable_data(
-                find_paths_unserializable_data(response, dump=const.JSON_DUMP)
+                find_paths_unserializable_data(response, dump=JSON_DUMP)
             ),
         )
     del response
@@ -330,14 +330,14 @@ def handle_subscribe_entities(
     cannot_serialize: list[str] = []
     for entity_id, state_dict in add_entities.items():
         try:
-            const.JSON_DUMP(state_dict)
+            JSON_DUMP(state_dict)
         except (ValueError, TypeError):
             cannot_serialize.append(entity_id)
 
     for entity_id in cannot_serialize:
         del add_entities[entity_id]
 
-    connection.send_message(const.JSON_DUMP(messages.event_message(msg["id"], data)))
+    connection.send_message(JSON_DUMP(messages.event_message(msg["id"], data)))
 
 
 @decorators.websocket_command({vol.Required("type"): "get_services"})
diff --git a/homeassistant/components/websocket_api/connection.py b/homeassistant/components/websocket_api/connection.py
index 0280863f83e..26c4c6f8321 100644
--- a/homeassistant/components/websocket_api/connection.py
+++ b/homeassistant/components/websocket_api/connection.py
@@ -11,6 +11,7 @@ import voluptuous as vol
 from homeassistant.auth.models import RefreshToken, User
 from homeassistant.core import Context, HomeAssistant, callback
 from homeassistant.exceptions import HomeAssistantError, Unauthorized
+from homeassistant.helpers.json import JSON_DUMP
 
 from . import const, messages
 
@@ -56,7 +57,7 @@ class ActiveConnection:
     async def send_big_result(self, msg_id: int, result: Any) -> None:
         """Send a result message that would be expensive to JSON serialize."""
         content = await self.hass.async_add_executor_job(
-            const.JSON_DUMP, messages.result_message(msg_id, result)
+            JSON_DUMP, messages.result_message(msg_id, result)
         )
         self.send_message(content)
 
diff --git a/homeassistant/components/websocket_api/const.py b/homeassistant/components/websocket_api/const.py
index 107cf6d0270..60a00126092 100644
--- a/homeassistant/components/websocket_api/const.py
+++ b/homeassistant/components/websocket_api/const.py
@@ -4,12 +4,9 @@ from __future__ import annotations
 import asyncio
 from collections.abc import Awaitable, Callable
 from concurrent import futures
-from functools import partial
-import json
 from typing import TYPE_CHECKING, Any, Final
 
 from homeassistant.core import HomeAssistant
-from homeassistant.helpers.json import JSONEncoder
 
 if TYPE_CHECKING:
     from .connection import ActiveConnection  # noqa: F401
@@ -53,10 +50,6 @@ SIGNAL_WEBSOCKET_DISCONNECTED: Final = "websocket_disconnected"
 # Data used to store the current connection list
 DATA_CONNECTIONS: Final = f"{DOMAIN}.connections"
 
-JSON_DUMP: Final = partial(
-    json.dumps, cls=JSONEncoder, allow_nan=False, separators=(",", ":")
-)
-
 COMPRESSED_STATE_STATE = "s"
 COMPRESSED_STATE_ATTRIBUTES = "a"
 COMPRESSED_STATE_CONTEXT = "c"
diff --git a/homeassistant/components/websocket_api/messages.py b/homeassistant/components/websocket_api/messages.py
index f546ba5eec6..c3e5f6bb5f5 100644
--- a/homeassistant/components/websocket_api/messages.py
+++ b/homeassistant/components/websocket_api/messages.py
@@ -9,6 +9,7 @@ import voluptuous as vol
 
 from homeassistant.core import Event, State
 from homeassistant.helpers import config_validation as cv
+from homeassistant.helpers.json import JSON_DUMP
 from homeassistant.util.json import (
     find_paths_unserializable_data,
     format_unserializable_data,
@@ -193,15 +194,15 @@ def compressed_state_dict_add(state: State) -> dict[str, Any]:
 def message_to_json(message: dict[str, Any]) -> str:
     """Serialize a websocket message to json."""
     try:
-        return const.JSON_DUMP(message)
+        return JSON_DUMP(message)
     except (ValueError, TypeError):
         _LOGGER.error(
             "Unable to serialize to JSON. Bad data found at %s",
             format_unserializable_data(
-                find_paths_unserializable_data(message, dump=const.JSON_DUMP)
+                find_paths_unserializable_data(message, dump=JSON_DUMP)
             ),
         )
-        return const.JSON_DUMP(
+        return JSON_DUMP(
             error_message(
                 message["id"], const.ERR_UNKNOWN_ERROR, "Invalid JSON in response"
             )
diff --git a/homeassistant/helpers/aiohttp_client.py b/homeassistant/helpers/aiohttp_client.py
index eaabb002b0a..2e56698db41 100644
--- a/homeassistant/helpers/aiohttp_client.py
+++ b/homeassistant/helpers/aiohttp_client.py
@@ -14,6 +14,7 @@ from aiohttp import web
 from aiohttp.hdrs import CONTENT_TYPE, USER_AGENT
 from aiohttp.web_exceptions import HTTPBadGateway, HTTPGatewayTimeout
 import async_timeout
+import orjson
 
 from homeassistant import config_entries
 from homeassistant.const import EVENT_HOMEASSISTANT_CLOSE, __version__
@@ -97,6 +98,7 @@ def _async_create_clientsession(
     """Create a new ClientSession with kwargs, i.e. for cookies."""
     clientsession = aiohttp.ClientSession(
         connector=_async_get_connector(hass, verify_ssl),
+        json_serialize=lambda x: orjson.dumps(x).decode("utf-8"),
         **kwargs,
     )
     # Prevent packages accidentally overriding our default headers
diff --git a/homeassistant/helpers/json.py b/homeassistant/helpers/json.py
index c581e5a9361..912667a13b5 100644
--- a/homeassistant/helpers/json.py
+++ b/homeassistant/helpers/json.py
@@ -1,7 +1,10 @@
 """Helpers to help with encoding Home Assistant objects in JSON."""
 import datetime
 import json
-from typing import Any
+from pathlib import Path
+from typing import Any, Final
+
+import orjson
 
 
 class JSONEncoder(json.JSONEncoder):
@@ -22,6 +25,20 @@ class JSONEncoder(json.JSONEncoder):
         return json.JSONEncoder.default(self, o)
 
 
+def json_encoder_default(obj: Any) -> Any:
+    """Convert Home Assistant objects.
+
+    Hand other objects to the original method.
+    """
+    if isinstance(obj, set):
+        return list(obj)
+    if hasattr(obj, "as_dict"):
+        return obj.as_dict()
+    if isinstance(obj, Path):
+        return obj.as_posix()
+    raise TypeError
+
+
 class ExtendedJSONEncoder(JSONEncoder):
     """JSONEncoder that supports Home Assistant objects and falls back to repr(o)."""
 
@@ -40,3 +57,31 @@ class ExtendedJSONEncoder(JSONEncoder):
             return super().default(o)
         except TypeError:
             return {"__type": str(type(o)), "repr": repr(o)}
+
+
+def json_bytes(data: Any) -> bytes:
+    """Dump json bytes."""
+    return orjson.dumps(
+        data, option=orjson.OPT_NON_STR_KEYS, default=json_encoder_default
+    )
+
+
+def json_dumps(data: Any) -> str:
+    """Dump json string.
+
+    orjson supports serializing dataclasses natively which
+    eliminates the need to implement as_dict in many places
+    when the data is already in a dataclass. This works
+    well as long as all the data in the dataclass can also
+    be serialized.
+
+    If it turns out to be a problem we can disable this
+    with option |= orjson.OPT_PASSTHROUGH_DATACLASS and it
+    will fallback to as_dict
+    """
+    return orjson.dumps(
+        data, option=orjson.OPT_NON_STR_KEYS, default=json_encoder_default
+    ).decode("utf-8")
+
+
+JSON_DUMP: Final = json_dumps
diff --git a/homeassistant/package_constraints.txt b/homeassistant/package_constraints.txt
index a3d8a00bcfb..c158d26a9aa 100644
--- a/homeassistant/package_constraints.txt
+++ b/homeassistant/package_constraints.txt
@@ -20,6 +20,7 @@ httpx==0.23.0
 ifaddr==0.1.7
 jinja2==3.1.2
 lru-dict==1.1.7
+orjson==3.6.8
 paho-mqtt==1.6.1
 pillow==9.1.1
 pip>=21.0,<22.2
diff --git a/homeassistant/scripts/benchmark/__init__.py b/homeassistant/scripts/benchmark/__init__.py
index a681b3e210d..efbfec5e961 100644
--- a/homeassistant/scripts/benchmark/__init__.py
+++ b/homeassistant/scripts/benchmark/__init__.py
@@ -12,14 +12,13 @@ from timeit import default_timer as timer
 from typing import TypeVar
 
 from homeassistant import core
-from homeassistant.components.websocket_api.const import JSON_DUMP
 from homeassistant.const import EVENT_STATE_CHANGED
 from homeassistant.helpers.entityfilter import convert_include_exclude_filter
 from homeassistant.helpers.event import (
     async_track_state_change,
     async_track_state_change_event,
 )
-from homeassistant.helpers.json import JSONEncoder
+from homeassistant.helpers.json import JSON_DUMP, JSONEncoder
 
 # mypy: allow-untyped-calls, allow-untyped-defs, no-check-untyped-defs
 # mypy: no-warn-return-any
diff --git a/homeassistant/util/json.py b/homeassistant/util/json.py
index fdee7a7a90f..82ecfd34d6d 100644
--- a/homeassistant/util/json.py
+++ b/homeassistant/util/json.py
@@ -7,6 +7,8 @@ import json
 import logging
 from typing import Any
 
+import orjson
+
 from homeassistant.core import Event, State
 from homeassistant.exceptions import HomeAssistantError
 
@@ -30,7 +32,7 @@ def load_json(filename: str, default: list | dict | None = None) -> list | dict:
     """
     try:
         with open(filename, encoding="utf-8") as fdesc:
-            return json.loads(fdesc.read())  # type: ignore[no-any-return]
+            return orjson.loads(fdesc.read())  # type: ignore[no-any-return]
     except FileNotFoundError:
         # This is not a fatal error
         _LOGGER.debug("JSON file not found: %s", filename)
@@ -56,7 +58,10 @@ def save_json(
     Returns True on success.
     """
     try:
-        json_data = json.dumps(data, indent=4, cls=encoder)
+        if encoder:
+            json_data = json.dumps(data, indent=2, cls=encoder)
+        else:
+            json_data = orjson.dumps(data, option=orjson.OPT_INDENT_2).decode("utf-8")
     except TypeError as error:
         msg = f"Failed to serialize to JSON: {filename}. Bad data at {format_unserializable_data(find_paths_unserializable_data(data))}"
         _LOGGER.error(msg)
diff --git a/pyproject.toml b/pyproject.toml
index cc745f58ad6..7e62bafd6af 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -41,6 +41,7 @@ dependencies    = [
     "PyJWT==2.4.0",
     # PyJWT has loose dependency. We want the latest one.
     "cryptography==36.0.2",
+    "orjson==3.6.8",
     "pip>=21.0,<22.2",
     "python-slugify==4.0.1",
     "pyyaml==6.0",
@@ -119,6 +120,7 @@ extension-pkg-allow-list = [
     "av.audio.stream",
     "av.stream",
     "ciso8601",
+    "orjson",
     "cv2",
 ]
 
diff --git a/requirements.txt b/requirements.txt
index fe2bf87ad25..9805ae7cd47 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -15,6 +15,7 @@ ifaddr==0.1.7
 jinja2==3.1.2
 PyJWT==2.4.0
 cryptography==36.0.2
+orjson==3.6.8
 pip>=21.0,<22.2
 python-slugify==4.0.1
 pyyaml==6.0
diff --git a/tests/components/energy/test_validate.py b/tests/components/energy/test_validate.py
index 37ebe4147c5..e802688daaf 100644
--- a/tests/components/energy/test_validate.py
+++ b/tests/components/energy/test_validate.py
@@ -4,6 +4,7 @@ from unittest.mock import patch
 import pytest
 
 from homeassistant.components.energy import async_get_manager, validate
+from homeassistant.helpers.json import JSON_DUMP
 from homeassistant.setup import async_setup_component
 
 
@@ -408,7 +409,11 @@ async def test_validation_grid(
         },
     )
 
-    assert (await validate.async_validate(hass)).as_dict() == {
+    result = await validate.async_validate(hass)
+    # verify its also json serializable
+    JSON_DUMP(result)
+
+    assert result.as_dict() == {
         "energy_sources": [
             [
                 {
diff --git a/tests/components/websocket_api/test_commands.py b/tests/components/websocket_api/test_commands.py
index 4d3302f7c13..0f4695596fc 100644
--- a/tests/components/websocket_api/test_commands.py
+++ b/tests/components/websocket_api/test_commands.py
@@ -619,12 +619,15 @@ async def test_states_filters_visible(hass, hass_admin_user, websocket_client):
 
 
 async def test_get_states_not_allows_nan(hass, websocket_client):
-    """Test get_states command not allows NaN floats."""
+    """Test get_states command converts NaN to None."""
     hass.states.async_set("greeting.hello", "world")
     hass.states.async_set("greeting.bad", "data", {"hello": float("NaN")})
     hass.states.async_set("greeting.bye", "universe")
 
     await websocket_client.send_json({"id": 5, "type": "get_states"})
+    bad = dict(hass.states.get("greeting.bad").as_dict())
+    bad["attributes"] = dict(bad["attributes"])
+    bad["attributes"]["hello"] = None
 
     msg = await websocket_client.receive_json()
     assert msg["id"] == 5
@@ -632,6 +635,7 @@ async def test_get_states_not_allows_nan(hass, websocket_client):
     assert msg["success"]
     assert msg["result"] == [
         hass.states.get("greeting.hello").as_dict(),
+        bad,
         hass.states.get("greeting.bye").as_dict(),
     ]