diff --git a/changelog.d/cat-ears.add b/changelog.d/cat-ears.add
new file mode 100644
index 0000000000..9b8f2fc958
--- /dev/null
+++ b/changelog.d/cat-ears.add
@@ -0,0 +1 @@
+Support `isCat` and `speakAsCat`
diff --git a/lib/pleroma/user.ex b/lib/pleroma/user.ex
index 468e124b5b..3aac910495 100644
--- a/lib/pleroma/user.ex
+++ b/lib/pleroma/user.ex
@@ -162,6 +162,8 @@ defmodule Pleroma.User do
     field(:birthday, :date)
     field(:show_birthday, :boolean, default: false)
     field(:language, :string)
+    field(:is_cat, :boolean, default: false)
+    field(:speak_as_cat, :boolean, default: false)
 
     embeds_one(
       :notification_settings,
@@ -527,7 +529,9 @@ defmodule Pleroma.User do
         :accepts_chat_messages,
         :pinned_objects,
         :birthday,
-        :show_birthday
+        :show_birthday,
+        :is_cat,
+        :speak_as_cat
       ]
     )
     |> cast(params, [:name], empty_values: [])
@@ -590,7 +594,9 @@ defmodule Pleroma.User do
         :accepts_chat_messages,
         :disclose_client,
         :birthday,
-        :show_birthday
+        :show_birthday,
+        :is_cat,
+        :speak_as_cat
       ]
     )
     |> validate_min_age()
diff --git a/lib/pleroma/web/activity_pub/activity_pub.ex b/lib/pleroma/web/activity_pub/activity_pub.ex
index 3e5239a286..63887793c0 100644
--- a/lib/pleroma/web/activity_pub/activity_pub.ex
+++ b/lib/pleroma/web/activity_pub/activity_pub.ex
@@ -1635,6 +1635,9 @@ defmodule Pleroma.Web.ActivityPub.ActivityPub do
 
     show_birthday = !!birthday
 
+    is_cat = Map.get(data, "isCat", false)
+    speak_as_cat = Map.get(data, "speakAsCat", is_cat)
+
     # if WebFinger request was already done, we probably have acct, otherwise
     # we request WebFinger here
     nickname = additional[:nickname_from_acct] || generate_nickname(data)
@@ -1663,7 +1666,9 @@ defmodule Pleroma.Web.ActivityPub.ActivityPub do
       birthday: birthday,
       show_birthday: show_birthday,
       pinned_objects: pinned_objects,
-      nickname: nickname
+      nickname: nickname,
+      is_cat: is_cat,
+      speak_as_cat: speak_as_cat
     }
   end
 
diff --git a/lib/pleroma/web/activity_pub/views/user_view.ex b/lib/pleroma/web/activity_pub/views/user_view.ex
index 61975387b3..186e2ed015 100644
--- a/lib/pleroma/web/activity_pub/views/user_view.ex
+++ b/lib/pleroma/web/activity_pub/views/user_view.ex
@@ -128,7 +128,9 @@ defmodule Pleroma.Web.ActivityPub.UserView do
       "alsoKnownAs" => user.also_known_as,
       "vcard:bday" => birthday,
       "webfinger" => "acct:#{User.full_nickname(user)}",
-      "published" => Pleroma.Web.CommonAPI.Utils.to_masto_date(user.inserted_at)
+      "published" => Pleroma.Web.CommonAPI.Utils.to_masto_date(user.inserted_at),
+      "isCat" => user.is_cat,
+      "speakAsCat" => user.speak_as_cat
     }
     |> Map.merge(
       maybe_make_image(
diff --git a/lib/pleroma/web/api_spec/operations/account_operation.ex b/lib/pleroma/web/api_spec/operations/account_operation.ex
index 5a19e0fbb7..637e097867 100644
--- a/lib/pleroma/web/api_spec/operations/account_operation.ex
+++ b/lib/pleroma/web/api_spec/operations/account_operation.ex
@@ -838,6 +838,16 @@ defmodule Pleroma.Web.ApiSpec.AccountOperation do
           type: :string,
           nullable: true,
           description: "Header image description."
+        },
+        is_cat: %Schema{
+          type: :boolean,
+          nullable: true,
+          description: "Whether the user is a cat"
+        },
+        speak_as_cat: %Schema{
+          type: :boolean,
+          nullable: true,
+          description: "Whether the user speaks as a cat"
         }
       },
       example: %{
diff --git a/lib/pleroma/web/api_spec/schemas/account.ex b/lib/pleroma/web/api_spec/schemas/account.ex
index 19827e9968..44084bc36d 100644
--- a/lib/pleroma/web/api_spec/schemas/account.ex
+++ b/lib/pleroma/web/api_spec/schemas/account.ex
@@ -114,7 +114,17 @@ defmodule Pleroma.Web.ApiSpec.Schemas.Account do
             description: "Favicon image of the user's instance"
           },
           avatar_description: %Schema{type: :string},
-          header_description: %Schema{type: :string}
+          header_description: %Schema{type: :string},
+          is_cat: %Schema{
+            type: :boolean,
+            nullable: true,
+            description: "Whether the user is a cat"
+          },
+          speak_as_cat: %Schema{
+            type: :boolean,
+            nullable: true,
+            description: "Whether the user speaks as a cat"
+          }
         }
       },
       source: %Schema{
@@ -211,7 +221,9 @@ defmodule Pleroma.Web.ApiSpec.Schemas.Account do
         "settings_store" => %{
           "pleroma-fe" => %{}
         },
-        "birthday" => "2001-02-12"
+        "birthday" => "2001-02-12",
+        "is_cat" => true,
+        "speak_as_cat" => true
       },
       "source" => %{
         "fields" => [],
diff --git a/lib/pleroma/web/mastodon_api/controllers/account_controller.ex b/lib/pleroma/web/mastodon_api/controllers/account_controller.ex
index d374e8c011..b0b6dd9128 100644
--- a/lib/pleroma/web/mastodon_api/controllers/account_controller.ex
+++ b/lib/pleroma/web/mastodon_api/controllers/account_controller.ex
@@ -202,7 +202,9 @@ defmodule Pleroma.Web.MastodonAPI.AccountController do
         :allow_following_move,
         :also_known_as,
         :accepts_chat_messages,
-        :show_birthday
+        :show_birthday,
+        :is_cat,
+        :speak_as_cat
       ]
       |> Enum.reduce(%{}, fn key, acc ->
         Maps.put_if_present(acc, key, params[key], &{:ok, Params.truthy_param?(&1)})
diff --git a/lib/pleroma/web/mastodon_api/views/account_view.ex b/lib/pleroma/web/mastodon_api/views/account_view.ex
index 03a2fc55a5..0695c1c485 100644
--- a/lib/pleroma/web/mastodon_api/views/account_view.ex
+++ b/lib/pleroma/web/mastodon_api/views/account_view.ex
@@ -325,7 +325,9 @@ defmodule Pleroma.Web.MastodonAPI.AccountView do
         accepts_chat_messages: user.accepts_chat_messages,
         favicon: favicon,
         avatar_description: avatar_description,
-        header_description: header_description
+        header_description: header_description,
+        is_cat: user.is_cat,
+        speak_as_cat: user.speak_as_cat
       }
     }
     |> maybe_put_role(user, opts[:for])
diff --git a/lib/pleroma/web/mastodon_api/views/instance_view.ex b/lib/pleroma/web/mastodon_api/views/instance_view.ex
index 1b6f26af72..8f5cdd18b5 100644
--- a/lib/pleroma/web/mastodon_api/views/instance_view.ex
+++ b/lib/pleroma/web/mastodon_api/views/instance_view.ex
@@ -158,7 +158,8 @@ defmodule Pleroma.Web.MastodonAPI.InstanceView do
       if Pleroma.Language.LanguageDetector.configured?() do
         "pleroma:language_detection"
       end,
-      "pleroma:block_expiration"
+      "pleroma:block_expiration",
+      "pleroma:is_cat"
     ]
     |> Enum.filter(& &1)
   end
diff --git a/priv/repo/migrations/20250402213700_add_is_cat_to_users.exs b/priv/repo/migrations/20250402213700_add_is_cat_to_users.exs
new file mode 100644
index 0000000000..4828b43253
--- /dev/null
+++ b/priv/repo/migrations/20250402213700_add_is_cat_to_users.exs
@@ -0,0 +1,10 @@
+defmodule Pleroma.Repo.Migrations.AddIsCatToUsers do
+  use Ecto.Migration
+
+  def change do
+    alter table(:users) do
+      add_if_not_exists(:is_cat, :boolean, default: false)
+      add_if_not_exists(:speak_as_cat, :boolean, default: false)
+    end
+  end
+end
diff --git a/priv/static/schemas/litepub-0.1.jsonld b/priv/static/schemas/litepub-0.1.jsonld
index 3569165a40..b6378a630b 100644
--- a/priv/static/schemas/litepub-0.1.jsonld
+++ b/priv/static/schemas/litepub-0.1.jsonld
@@ -43,7 +43,11 @@
             "vcard": "http://www.w3.org/2006/vcard/ns#",
             "formerRepresentations": "litepub:formerRepresentations",
             "sm": "http://smithereen.software/ns#",
-            "nonAnonymous": "sm:nonAnonymous"
+            "nonAnonymous": "sm:nonAnonymous",
+            "misskey": "https://misskey-hub.net/ns#",
+            "isCat": "misskey:isCat",
+            "firefish": "https://joinfirefish.org/ns#",
+            "speakAsCat": "firefish:speakAsCat"
         }
     ]
 }
diff --git a/test/pleroma/web/activity_pub/activity_pub_test.exs b/test/pleroma/web/activity_pub/activity_pub_test.exs
index 7fc4f47cd6..54d8f5dbb8 100644
--- a/test/pleroma/web/activity_pub/activity_pub_test.exs
+++ b/test/pleroma/web/activity_pub/activity_pub_test.exs
@@ -2754,4 +2754,112 @@ defmodule Pleroma.Web.ActivityPub.ActivityPubTest do
                "first" => "https://social.example/users/alice/collections/featured?page=true"
              })
   end
+
+  describe "cat ears" do
+    test "it respects isCat and speakAsCat" do
+      cat_id = "https://example.com/users/cat"
+
+      cat_data =
+        "test/fixtures/users_mock/user.json"
+        |> File.read!()
+        |> String.replace("{{nickname}}", "cat")
+        |> Jason.decode!()
+        |> Map.delete("featured")
+        |> Map.put("isCat", true)
+        |> Map.put("speakAsCat", true)
+        |> Jason.encode!()
+
+      dog_id = "https://example.com/users/dog"
+
+      dog_data =
+        "test/fixtures/users_mock/user.json"
+        |> File.read!()
+        |> String.replace("{{nickname}}", "dog")
+        |> Jason.decode!()
+        |> Map.delete("featured")
+        |> Map.put("isCat", false)
+        |> Map.put("speakAsCat", false)
+        |> Jason.encode!()
+
+      Tesla.Mock.mock(fn
+        %{
+          method: :get,
+          url: ^cat_id
+        } ->
+          %Tesla.Env{
+            status: 200,
+            body: cat_data,
+            headers: [{"content-type", "application/activity+json"}]
+          }
+
+        %{
+          method: :get,
+          url: ^dog_id
+        } ->
+          %Tesla.Env{
+            status: 200,
+            body: dog_data,
+            headers: [{"content-type", "application/activity+json"}]
+          }
+      end)
+
+      {:ok, cat} = ActivityPub.make_user_from_ap_id(cat_id)
+      {:ok, dog} = ActivityPub.make_user_from_ap_id(dog_id)
+
+      assert %{is_cat: true, speak_as_cat: true} = cat
+      assert %{is_cat: false, speak_as_cat: false} = dog
+    end
+
+    test "it infers speakAsCat from isCat, when missing" do
+      cat_id = "https://example.com/users/cat"
+
+      cat_data =
+        "test/fixtures/users_mock/user.json"
+        |> File.read!()
+        |> String.replace("{{nickname}}", "cat")
+        |> Jason.decode!()
+        |> Map.delete("featured")
+        |> Map.put("isCat", true)
+        |> Jason.encode!()
+
+      dog_id = "https://example.com/users/dog"
+
+      dog_data =
+        "test/fixtures/users_mock/user.json"
+        |> File.read!()
+        |> String.replace("{{nickname}}", "dog")
+        |> Jason.decode!()
+        |> Map.delete("featured")
+        |> Map.put("isCat", false)
+        |> Jason.encode!()
+
+      Tesla.Mock.mock(fn
+        %{
+          method: :get,
+          url: ^cat_id
+        } ->
+          %Tesla.Env{
+            status: 200,
+            body: cat_data,
+            headers: [{"content-type", "application/activity+json"}]
+          }
+
+        %{
+          method: :get,
+          url: ^dog_id
+        } ->
+          %Tesla.Env{
+            status: 200,
+            body: dog_data,
+            headers: [{"content-type", "application/activity+json"}]
+          }
+      end)
+
+      {:ok, cat} = ActivityPub.make_user_from_ap_id(cat_id)
+      {:ok, dog} = ActivityPub.make_user_from_ap_id(dog_id)
+
+      assert %{is_cat: true, speak_as_cat: true} = cat
+      assert %{is_cat: false, speak_as_cat: false} = dog
+    end
+  end
 end
diff --git a/test/pleroma/web/mastodon_api/update_credentials_test.exs b/test/pleroma/web/mastodon_api/update_credentials_test.exs
index 97ad2e849f..bb90ab1b25 100644
--- a/test/pleroma/web/mastodon_api/update_credentials_test.exs
+++ b/test/pleroma/web/mastodon_api/update_credentials_test.exs
@@ -823,4 +823,19 @@ defmodule Pleroma.Web.MastodonAPI.UpdateCredentialsTest do
       assert account["source"]["pleroma"]["actor_type"] == "Group"
     end
   end
+
+  describe "cat ears" do
+    setup do: oauth_access(["write:accounts"])
+    setup :request_content_type
+
+    test "sets cat ears preferences", %{conn: conn} do
+      account =
+        conn
+        |> patch("/api/v1/accounts/update_credentials", %{is_cat: true, speak_as_cat: false})
+        |> json_response_and_validate_schema(200)
+
+      assert account["pleroma"]["is_cat"]
+      assert not account["pleroma"]["speak_as_cat"]
+    end
+  end
 end
diff --git a/test/pleroma/web/mastodon_api/views/account_view_test.exs b/test/pleroma/web/mastodon_api/views/account_view_test.exs
index 5d24c0e9fb..c0591e93a7 100644
--- a/test/pleroma/web/mastodon_api/views/account_view_test.exs
+++ b/test/pleroma/web/mastodon_api/views/account_view_test.exs
@@ -98,7 +98,9 @@ defmodule Pleroma.Web.MastodonAPI.AccountViewTest do
         skip_thread_containment: false,
         accepts_chat_messages: nil,
         avatar_description: "",
-        header_description: ""
+        header_description: "",
+        is_cat: false,
+        speak_as_cat: false
       }
     }
 
@@ -344,7 +346,9 @@ defmodule Pleroma.Web.MastodonAPI.AccountViewTest do
         skip_thread_containment: false,
         accepts_chat_messages: nil,
         avatar_description: "",
-        header_description: ""
+        header_description: "",
+        is_cat: false,
+        speak_as_cat: false
       }
     }
 
@@ -845,4 +849,17 @@ defmodule Pleroma.Web.MastodonAPI.AccountViewTest do
              DateTime.utc_now() |> DateTime.add(24 * 60 * 60)
            ) in -3..3
   end
+
+  test "renders isCat and speakAsCat" do
+    cat = insert(:user, is_cat: true, speak_as_cat: true)
+    dog = insert(:user, is_cat: false, speak_as_cat: false)
+
+    %{
+      pleroma: %{is_cat: true, speak_as_cat: true}
+    } = AccountView.render("show.json", %{user: cat, skip_visibility_check: true})
+
+    %{
+      pleroma: %{is_cat: false, speak_as_cat: false}
+    } = AccountView.render("show.json", %{user: dog, skip_visibility_check: true})
+  end
 end