diff --git a/.changeset/tidy-bags-fix.md b/.changeset/tidy-bags-fix.md
new file mode 100644
index 0000000..62c93d3
--- /dev/null
+++ b/.changeset/tidy-bags-fix.md
@@ -0,0 +1,5 @@
+---
+'@0no-co/graphql.web': patch
+---
+
+Allow `undefined` on `DocumentNode.tokenCount` to preserve compatibility with `graphql` when `exactOptionalPropertyTypes` is enabled.
diff --git a/src/ast.ts b/src/ast.ts
index c04df5a..817cada 100644
--- a/src/ast.ts
+++ b/src/ast.ts
@@ -99,12 +99,12 @@ export type NameNode = Or<
 >;
 
 export type DocumentNode = Or<
-  GraphQL.DocumentNode & { readonly tokenCount?: number },
+  GraphQL.DocumentNode & { readonly tokenCount?: number | undefined },
   {
     readonly kind: Kind.DOCUMENT;
     readonly definitions: ReadonlyArray<DefinitionNode>;
     readonly loc?: Location;
-    readonly tokenCount?: number;
+    readonly tokenCount?: number | undefined;
   }
 >;