diff --git a/README.md b/README.md
index eb7baa6..2b10515 100644
--- a/README.md
+++ b/README.md
@@ -37,6 +37,7 @@ swaggerOptions: { // passed to SwaggerUi()
   defaultModelRendering: 'schema',
   showRequestHeaders: false,
   swaggerVersion: 'x.x.x' // read from package.json,
+  validatorUrl: null, // disable swagger-ui validator
 },
 routePrefix: '/docs', // route where the view is returned
 specPrefix: '/docs/spec', // route where the spec is returned
diff --git a/lib/index.ts b/lib/index.ts
index cc2e81a..6df45c7 100644
--- a/lib/index.ts
+++ b/lib/index.ts
@@ -6,22 +6,23 @@ import { sync as readPkgUpSync } from 'read-pkg-up';
 import { Context, Middleware, Next } from 'koa';
 
 export interface SwaggerOptions {
-  [key: string]: string | boolean | string[] | Record<string, unknown>;
-  dom_id: string;
-  url: string;
-  supportedSubmitMethods: string[];
-  docExpansion: string;
-  jsonEditor: boolean;
-  defaultModelRendering: string;
-  showRequestHeaders: boolean;
-  layout: string;
-  spec: Record<string, unknown>;
+  [key: string]: string | boolean | string[] | Record<string, unknown> | null | undefined;
+  dom_id?: string;
+  url?: string;
+  supportedSubmitMethods?: string[];
+  docExpansion?: string;
+  jsonEditor?: boolean;
+  defaultModelRendering?: string;
+  showRequestHeaders?: boolean;
+  layout?: string;
+  spec?: Record<string, unknown>;
+  validatorUrl?: string | null;
 }
 
 export interface KoaSwaggerUiOptions {
   title: string;
   oauthOptions: boolean | any;
-  swaggerOptions: Partial<SwaggerOptions>;
+  swaggerOptions: SwaggerOptions;
   swaggerVersion: string;
   routePrefix: string | false;
   specPrefix: string;
diff --git a/test/example.ts b/test/example.ts
index a599886..1d7ccfe 100644
--- a/test/example.ts
+++ b/test/example.ts
@@ -8,7 +8,10 @@ const router = new KoaRouter();
 
 app.use(koaSwagger({
   exposeSpec: true,
-  swaggerOptions: { spec: {} },
+  swaggerOptions: {
+    spec: {},
+    validatorUrl: null,
+  },
 }));
 
 export default app;