diff --git a/packages/conform-zod/coercion.ts b/packages/conform-zod/coercion.ts
index 6f492625..9c46f335 100644
--- a/packages/conform-zod/coercion.ts
+++ b/packages/conform-zod/coercion.ts
@@ -55,7 +55,12 @@ export function coerceString(
  * Modify the value only if it's a file, otherwise return the value as-is
  */
 export function coerceFile(file: unknown) {
-	if (file instanceof File && file.name === '' && file.size === 0) {
+	if (
+		typeof File !== 'undefined' &&
+		file instanceof File &&
+		file.name === '' &&
+		file.size === 0
+	) {
 		return undefined;
 	}
 
@@ -68,6 +73,10 @@ export function coerceFile(file: unknown) {
  * Check the `instanceOfType` function on zod for more info
  */
 export function isFileSchema(schema: ZodEffects<any, any, any>): boolean {
+	if (typeof File === 'undefined') {
+		return false;
+	}
+
 	return (
 		schema._def.effect.type === 'refinement' &&
 		schema.innerType() instanceof ZodAny &&
diff --git a/tests/conform-zod.spec.ts b/tests/conform-zod.spec.ts
index 60b59112..71a3a2b7 100644
--- a/tests/conform-zod.spec.ts
+++ b/tests/conform-zod.spec.ts
@@ -13,7 +13,7 @@ function createFormData(entries: Array<[string, string | File]>): FormData {
 	return formData;
 }
 
-test.beforeAll(() => {
+test.beforeEach(() => {
 	installGlobals();
 });
 
@@ -660,6 +660,11 @@ test.describe('conform-zod', () => {
 				},
 				error: {},
 			});
+
+			// @ts-expect-error To test if File is not defined in certain environment
+			delete global.File;
+
+			expect(() => parse(createFormData([]), { schema })).not.toThrow();
 		});
 
 		test('z.lazy', () => {