diff --git a/src/context.ts b/src/context.ts
index 0f862dbc..f96c91e0 100644
--- a/src/context.ts
+++ b/src/context.ts
@@ -12,7 +12,8 @@ import type {
 	Prettify,
 	ResolvePath,
 	SingletonBase,
-	HTTPHeaders
+	HTTPHeaders,
+	IsSkipped
 } from './types'
 
 type InvertedStatusMapKey = keyof InvertedStatusMap
@@ -29,18 +30,18 @@ export type ErrorContext<
 > = Prettify<
 	{
 		body: Route['body']
-		query: undefined extends Route['query']
+		query: IsSkipped<Route['query']> extends true
 			? Record<string, string | undefined>
 			: Route['query']
-		params: undefined extends Route['params']
+		params: IsSkipped<Route['params']> extends true
 			? Path extends `${string}/${':' | '*'}${string}`
 				? ResolvePath<Path>
 				: { [key in string]: string }
 			: Route['params']
-		headers: undefined extends Route['headers']
+		headers: IsSkipped<Route['headers']> extends true
 			? Record<string, string | undefined>
 			: Route['headers']
-		cookie: undefined extends Route['cookie']
+		cookie: IsSkipped<Route['cookie']> extends true
 			? Record<string, Cookie<string | undefined>>
 			: Record<string, Cookie<string | undefined>> & {
 					[key in keyof Route['cookie']]-?: NonNullable<
@@ -122,20 +123,20 @@ export type Context<
 > = Prettify<
 	{
 		body: PrettifyIfObject<Route['body']>
-		query: undefined extends Route['query']
+		query: IsSkipped<Route['query']> extends true
 			? Record<string, string>
 			: PrettifyIfObject<Route['query']>
-		params: undefined extends Route['params']
+		params: IsSkipped<Route['params']> extends true
 			? undefined extends Path
 				? Record<string, string>
 				: Path extends `${string}/${':' | '*'}${string}`
 					? ResolvePath<Path>
 					: never
 			: PrettifyIfObject<Route['params']>
-		headers: undefined extends Route['headers']
+		headers: IsSkipped<Route['headers']> extends true
 			? Record<string, string | undefined>
 			: PrettifyIfObject<Route['headers']>
-		cookie: undefined extends Route['cookie']
+		cookie: IsSkipped<Route['cookie']> extends true
 			? Record<string, Cookie<string | undefined>>
 			: Record<string, Cookie<string | undefined>> & {
 					[key in keyof Route['cookie']]-?: Cookie<
diff --git a/src/type-system/index.ts b/src/type-system/index.ts
index 009980bd..68dc1ee3 100644
--- a/src/type-system/index.ts
+++ b/src/type-system/index.ts
@@ -419,6 +419,12 @@ export const ElysiaType = {
 	MaybeEmpty: <T extends TSchema>(schema: T, options?: SchemaOptions) =>
 		t.Union([schema, t.Null(), t.Undefined()], options),
 
+	/**
+	 * Allow Optional and Undefined
+	 */
+	Undefinable: <T extends TSchema>(schema: T, options?: SchemaOptions) =>
+		t.Union([schema, t.Undefined()], options),
+
 	Cookie: <T extends TProperties>(
 		properties: T,
 		{
@@ -574,6 +580,7 @@ t.Files = (arg) => {
 
 t.Nullable = ElysiaType.Nullable
 t.MaybeEmpty = ElysiaType.MaybeEmpty
+t.Undefinable = ElysiaType.Undefinable
 t.Cookie = ElysiaType.Cookie
 t.Date = ElysiaType.Date
 t.UnionEnum = ElysiaType.UnionEnum
diff --git a/src/types.ts b/src/types.ts
index 0dec442a..4bf4e145 100644
--- a/src/types.ts
+++ b/src/types.ts
@@ -654,9 +654,9 @@ export interface MergeSchema<
 	in out B extends RouteSchema,
 	Path extends string = ''
 > {
-	body: undefined extends A['body'] ? B['body'] : A['body']
-	headers: undefined extends A['headers'] ? B['headers'] : A['headers']
-	query: undefined extends A['query'] ? B['query'] : A['query']
+	body: IsSkipped<A['body']> extends true ? B['body'] : A['body']
+	headers: IsSkipped<A['headers']> extends true ? B['headers'] : A['headers']
+	query: IsSkipped<A['query']> extends true ? B['query'] : A['query']
 	params: IsNever<keyof A['params']> extends true
 		? IsNever<keyof B['params']> extends true
 			? ResolvePath<Path>
@@ -679,25 +679,25 @@ export interface MergeStandaloneSchema<
 	in out B extends RouteSchema,
 	Path extends string = ''
 > {
-	body: undefined extends A['body']
-		? undefined extends B['body']
+	body: IsSkipped<A['body']> extends true
+		? IsSkipped<B['body']> extends true
 			? undefined
 			: B['body']
-		: undefined extends B['body']
+		: IsSkipped<B['body']> extends true
 			? A['body']
 			: Prettify<A['body'] & B['body']>
-	headers: undefined extends A['headers']
-		? undefined extends B['headers']
+	headers: IsSkipped<A['headers']> extends true
+		? IsSkipped<B['headers']> extends true
 			? undefined
 			: B['headers']
-		: undefined extends B['headers']
+		: IsSkipped<B['headers']> extends true
 			? A['headers']
 			: Prettify<A['headers'] & B['headers']>
-	query: undefined extends A['query']
-		? undefined extends B['query']
+	query: IsSkipped<A['query']> extends true
+		? IsSkipped<B['query']> extends true
 			? undefined
 			: B['query']
-		: undefined extends B['query']
+		: IsSkipped<B['query']> extends true
 			? A['query']
 			: Prettify<A['query'] & B['query']>
 	params: IsNever<keyof A['params']> extends true
@@ -707,11 +707,11 @@ export interface MergeStandaloneSchema<
 		: IsNever<keyof B['params']> extends true
 			? A['params']
 			: Prettify<A['params'] & B['params']>
-	cookie: undefined extends A['cookie']
-		? undefined extends B['cookie']
+	cookie: IsSkipped<A['cookie']> extends true
+		? IsSkipped<B['cookie']> extends true
 			? undefined
 			: B['cookie']
-		: undefined extends B['cookie']
+		: IsSkipped<B['cookie']> extends true
 			? A['cookie']
 			: Prettify<A['cookie'] & B['cookie']>
 	response: {} extends A['response']
@@ -742,6 +742,16 @@ export type Handler<
 
 export type IsAny<T> = 0 extends 1 & T ? true : false
 
+export type IsUnknown<T> = IsAny<T> extends true
+    ? false
+    : unknown extends T
+    ? true
+    : false
+
+export type IsUndefined<T> = [T] extends [undefined] ? true : false;
+
+export type IsSkipped<T> = IsUnknown<T> extends true ? true : IsUndefined<T> extends true ? true : false;
+
 export type Replace<Original, Target, With> =
 	IsAny<Target> extends true
 		? Original
diff --git a/test/types/index.ts b/test/types/index.ts
index feff09ee..0759d6a3 100644
--- a/test/types/index.ts
+++ b/test/types/index.ts
@@ -2671,3 +2671,19 @@ type a = keyof {}
 		(typeof app)['~Routes']['get']['response'][200]
 	>().toEqualTypeOf<AsyncGenerator<'a', void, unknown>>()
 }
+
+// infer Undefinable query, headers and body correctly
+{
+	const app = new Elysia().post("/", ({ query: { name = 'Elysia' } = {} }) => {
+		return `Hello ${name}`;
+	}, {
+		query: t.Undefinable(t.Object({ name: t.String() })),
+		headers: t.Undefinable(t.Object({ token: t.String() })),
+		body: t.Undefinable(t.Object({ id: t.Number() })),
+	});
+
+	expectTypeOf(app["~Routes"].post.query).not.toEqualTypeOf<unknown>();
+	expectTypeOf(app["~Routes"].post.query).toEqualTypeOf<{ name: string } | undefined>();
+	expectTypeOf(app["~Routes"].post.headers).toEqualTypeOf<{ token: string } | undefined>();
+	expectTypeOf(app["~Routes"].post.body).toEqualTypeOf<{ id: number } | undefined>();
+}
\ No newline at end of file