diff --git a/app/components/Edit/EditTodoSheet.vue b/app/components/Edit/EditTodoSheet.vue
index 53d8ffb..36e2d87 100644
--- a/app/components/Edit/EditTodoSheet.vue
+++ b/app/components/Edit/EditTodoSheet.vue
@@ -49,6 +49,8 @@
 
 	const { mutate: updateTodo } = useUpdateTodo();
 	async function onSaveTodo() {
+		if (!isValid.value) return;
+
 		updateTodo({ uuid: uuid.value, todoData: todoData.value });
 
 		showSaveIcon.value = false;
@@ -65,7 +67,9 @@
 	}
 
 	const isValid = computed(() => {
-		return todoData.value.title !== "";
+		if (todoData.value.title === "") return false;
+
+		return !isTodoSame(todoData.value, uuid.value);
 	});
 
 	const { mutate: deleteTodo } = useDeleteTodo();
diff --git a/app/composables/useTodoUtils.ts b/app/composables/useTodoUtils.ts
index bb54d45..1c17076 100644
--- a/app/composables/useTodoUtils.ts
+++ b/app/composables/useTodoUtils.ts
@@ -1,5 +1,46 @@
+import { dequal } from "dequal";
+
+import { toRaw } from "vue";
 import { useTodosQuery } from "~/queries/todo";
 
+export function isTodoSame(todo: CreateTodoData, uuid: UUID): boolean {
+	const otherTodo = useTodoById(uuid);
+
+	// 1. Guard against missing target
+	if (!otherTodo) return false;
+
+	// 2. Primitive comparisons
+	if ((todo.title ?? "") !== (otherTodo.title ?? "")) return false;
+	if ((todo.note ?? "") !== (otherTodo.note ?? "")) return false;
+
+	// 3. Complex Object comparison (handles key order + reactive proxies)
+	const rawTimeA = todo.time ? toRaw(todo.time) : undefined;
+	const rawTimeB = otherTodo.time ? toRaw(otherTodo.time) : undefined;
+	if (!dequal(rawTimeA, rawTimeB)) return false;
+
+	// 4. Category check
+	if ((todo.category ?? undefined) !== (otherTodo.category?.uuid ?? undefined))
+		return false;
+
+	// 5. Tags comparison
+	const tagsA = todo.tags ?? [];
+	const tagsB = otherTodo.tags?.map((t) => t.uuid) ?? [];
+
+	if (tagsA.length !== tagsB.length) return false;
+	const tagSetB = new Set(tagsB);
+	if (!tagsA.every((tag) => tagSetB.has(tag))) return false;
+
+	// 6. Reminders comparison check if exists
+	if (
+		(todo.reminders?.length ?? 0) !== 0 ||
+		(otherTodo?.reminders?.length ?? 0) !== 0
+	) {
+		return false;
+	}
+
+	return true;
+}
+
 export function useTodoById(uuid: UUID) {
 	const queryCache = useQueryCache();
 	const todos = queryCache.getQueryData(useTodosQuery().key);
diff --git a/flake.nix b/flake.nix
index 5dbbbaf..b0eca03 100644
--- a/flake.nix
+++ b/flake.nix
@@ -88,7 +88,7 @@
               inherit (finalAttrs) pname version src;
               inherit pnpm;
               fetcherVersion = 4;
-              hash = "sha256-+Ij7VYLQeamCaoQntmfaDLDOJ14+upzUg/CDcLkPImI=";
+              hash = "sha256-hlTOJkw0FEHnEsc4DaW3CmQHQV82BObQgh3cRD0BI0A=";
             };
 
             buildPhase = ''
diff --git a/package.json b/package.json
index e2c88ed..cdaa34f 100644
--- a/package.json
+++ b/package.json
@@ -31,6 +31,7 @@
 		"@pinia/nuxt": "^1.0.2",
 		"@vueuse/nuxt": "^14.4.0",
 		"better-auth": "^1.7.4",
+		"dequal": "^2.0.3",
 		"marked": "^18.0.12",
 		"nuxt": "^4.5.2",
 		"pg": "^8.23.0",
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index 79b229e..176e3ac 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -44,6 +44,9 @@ importers:
       better-auth:
         specifier: ^1.7.4
         version: 1.7.4(pg@8.23.0)(vitest@4.1.11(@types/node@22.20.2)(happy-dom@20.14.3)(vite@8.3.0(@types/node@22.20.2)(esbuild@0.28.2)(jiti@2.7.0)(terser@5.51.2)(yaml@2.9.0)))(vue@3.5.42(typescript@6.0.3))
+      dequal:
+        specifier: ^2.0.3
+        version: 2.0.3
       marked:
         specifier: ^18.0.12
         version: 18.0.12
@@ -2701,6 +2704,10 @@ packages:
     resolution: {integrity: sha512-g7nH6P6dyDioJogAAGprGpCtVImJhpPk/roCzdb3fIh61/s/nPsfR6onyMwkCAR/OlC3yBC0lESvUoQEAssIrw==}
     engines: {node: '>= 0.8'}
 
+  dequal@2.0.3:
+    resolution: {integrity: sha512-0je+qPKHEMohvfRTCEo3CrPG6cAzAYgmzKyxRiYSSDkS6eGJdyVJm7WaYA5ECaAD9wLB2T4EEeymA5aFVcYXCA==}
+    engines: {node: '>=6'}
+
   destr@2.0.5:
     resolution: {integrity: sha512-ugFTXCtDZunbzasqBxrK93Ik/DRYsO6S/fedkWEMKqt04xZ4csmnmwGDBAb07QWNaGMAmnTIemsYZCksjATwsA==}
 
@@ -7678,6 +7685,8 @@ snapshots:
 
   depd@2.0.0: {}
 
+  dequal@2.0.3: {}
+
   destr@2.0.5: {}
 
   detect-libc@2.1.2: {}