diff --git a/packages/api/src/dto/application.test.ts b/packages/api/src/dto/application.test.ts
index b91108b73..ed3ad7410 100644
--- a/packages/api/src/dto/application.test.ts
+++ b/packages/api/src/dto/application.test.ts
@@ -83,3 +83,24 @@ describe("applicationDto zero-argument inputs", () => {
 		expect(applicationDto.tags.input.parse(undefined)).toEqual({});
 	});
 });
+
+// Bulk operations cap `ids` at 200 to bound memory/DB work from a single call.
+describe("applicationDto bulk id caps", () => {
+	const idsOfLength = (n: number) => Array.from({ length: n }, (_, i) => String(i));
+
+	it("rejects a bulkDelete ids array over the cap", () => {
+		expect(applicationDto.bulkDelete.input.safeParse({ ids: idsOfLength(201) }).success).toBe(false);
+	});
+
+	it("accepts a bulkDelete ids array at the cap", () => {
+		expect(applicationDto.bulkDelete.input.safeParse({ ids: idsOfLength(200) }).success).toBe(true);
+	});
+
+	it("rejects a bulkUpdate ids array over the cap", () => {
+		expect(applicationDto.bulkUpdate.input.safeParse({ ids: idsOfLength(201) }).success).toBe(false);
+	});
+
+	it("accepts a bulkUpdate ids array at the cap", () => {
+		expect(applicationDto.bulkUpdate.input.safeParse({ ids: idsOfLength(200) }).success).toBe(true);
+	});
+});
diff --git a/packages/api/src/dto/application.ts b/packages/api/src/dto/application.ts
index 0fc0753fb..9f9e26255 100644
--- a/packages/api/src/dto/application.ts
+++ b/packages/api/src/dto/application.ts
@@ -162,7 +162,7 @@ export const applicationDto = {
 	// Table bulk actions: move stage, archive/unarchive, add tags across a selection.
 	bulkUpdate: {
 		input: z.object({
-			ids: z.array(z.string()).min(1),
+			ids: z.array(z.string()).min(1).max(200, "Too many items in a single bulk operation"),
 			status: applicationStatusSchema.optional(),
 			archived: z.boolean().optional(),
 			addTags: z.array(z.string()).optional(),
@@ -171,7 +171,7 @@ export const applicationDto = {
 	},
 
 	bulkDelete: {
-		input: z.object({ ids: z.array(z.string()).min(1) }),
+		input: z.object({ ids: z.array(z.string()).min(1).max(200, "Too many items in a single bulk operation") }),
 		output: z.object({ deleted: z.number() }),
 	},