diff --git a/crates/oxc_parser/src/js/arrow.rs b/crates/oxc_parser/src/js/arrow.rs
index 632d5cc71f72d..4f536b8ab2cb5 100644
--- a/crates/oxc_parser/src/js/arrow.rs
+++ b/crates/oxc_parser/src/js/arrow.rs
@@ -79,7 +79,7 @@ impl<'a> ParserImpl<'a> {
                     Kind::RParen => {
                         let third = self.nth_kind(offset + 2);
                         return match third {
-                            Kind::Colon if self.ts_enabled() => Tristate::Maybe,
+                            Kind::Colon if self.is_ts => Tristate::Maybe,
                             Kind::Arrow | Kind::LCurly => Tristate::True,
                             _ => Tristate::False,
                         };
diff --git a/crates/oxc_parser/src/js/binding.rs b/crates/oxc_parser/src/js/binding.rs
index af0b05cddf707..07df82ee1c984 100644
--- a/crates/oxc_parser/src/js/binding.rs
+++ b/crates/oxc_parser/src/js/binding.rs
@@ -19,8 +19,7 @@ impl<'a> ParserImpl<'a> {
         allow_question: bool,
     ) -> Result<BindingPattern<'a>> {
         let mut kind = self.parse_binding_pattern_kind()?;
-        let optional =
-            if allow_question && self.ts_enabled() { self.eat(Kind::Question) } else { false };
+        let optional = if allow_question && self.is_ts { self.eat(Kind::Question) } else { false };
         let type_annotation = self.parse_ts_type_annotation()?;
         if let Some(type_annotation) = &type_annotation {
             Self::extend_binding_pattern_span_end(type_annotation.span, &mut kind);
@@ -111,7 +110,7 @@ impl<'a> ParserImpl<'a> {
 
         let kind = self.parse_binding_pattern_kind()?;
         // Rest element does not allow `?`, checked in checker/typescript.rs
-        if self.at(Kind::Question) && self.ts_enabled() {
+        if self.at(Kind::Question) && self.is_ts {
             let span = self.cur_token().span();
             self.bump_any();
             self.error(diagnostics::a_rest_parameter_cannot_be_optional(span));
diff --git a/crates/oxc_parser/src/js/class.rs b/crates/oxc_parser/src/js/class.rs
index d8ed536cf7bb4..089bd49e04b63 100644
--- a/crates/oxc_parser/src/js/class.rs
+++ b/crates/oxc_parser/src/js/class.rs
@@ -75,8 +75,7 @@ impl<'a> ParserImpl<'a> {
             None
         };
 
-        let type_parameters =
-            if self.ts_enabled() { self.parse_ts_type_parameters()? } else { None };
+        let type_parameters = if self.is_ts { self.parse_ts_type_parameters()? } else { None };
         let (extends, implements) = self.parse_heritage_clause()?;
         let mut super_class = None;
         let mut super_type_parameters = None;
@@ -283,7 +282,7 @@ impl<'a> ParserImpl<'a> {
 
         if let PropertyKey::PrivateIdentifier(private_ident) = &key {
             // `private #foo`, etc. is illegal
-            if self.ts_enabled() {
+            if self.is_ts {
                 self.verify_modifiers(
                     &modifiers,
                     ModifierFlags::all() - ModifierFlags::ACCESSIBILITY,
@@ -457,8 +456,7 @@ impl<'a> ParserImpl<'a> {
         optional: bool,
         definite: bool,
     ) -> Result<ClassElement<'a>> {
-        let type_annotation =
-            if self.ts_enabled() { self.parse_ts_type_annotation()? } else { None };
+        let type_annotation = if self.is_ts { self.parse_ts_type_annotation()? } else { None };
         let decorators = self.consume_decorators();
         let value = if self.eat(Kind::Eq) { Some(self.parse_expr()?) } else { None };
         self.asi()?;
@@ -506,8 +504,7 @@ impl<'a> ParserImpl<'a> {
         definite: bool,
         accessibility: Option<TSAccessibility>,
     ) -> Result<ClassElement<'a>> {
-        let type_annotation =
-            if self.ts_enabled() { self.parse_ts_type_annotation()? } else { None };
+        let type_annotation = if self.is_ts { self.parse_ts_type_annotation()? } else { None };
         let value =
             self.eat(Kind::Eq).then(|| self.parse_assignment_expression_or_higher()).transpose()?;
         let r#type = if r#abstract {
diff --git a/crates/oxc_parser/src/js/declaration.rs b/crates/oxc_parser/src/js/declaration.rs
index b7d4757b82ca6..ab8f87132e367 100644
--- a/crates/oxc_parser/src/js/declaration.rs
+++ b/crates/oxc_parser/src/js/declaration.rs
@@ -95,7 +95,7 @@ impl<'a> ParserImpl<'a> {
 
         let mut binding_kind = self.parse_binding_pattern_kind()?;
 
-        let (id, definite) = if self.ts_enabled() {
+        let (id, definite) = if self.is_ts {
             // const x!: number = 1
             //        ^ definite
             let mut definite = false;
diff --git a/crates/oxc_parser/src/js/expression.rs b/crates/oxc_parser/src/js/expression.rs
index f028f08172052..3edbf02f0230e 100644
--- a/crates/oxc_parser/src/js/expression.rs
+++ b/crates/oxc_parser/src/js/expression.rs
@@ -644,7 +644,7 @@ impl<'a> ParserImpl<'a> {
                         _ => break,
                     }
                 }
-                Kind::Bang if !self.cur_token().is_on_new_line && self.ts_enabled() => {
+                Kind::Bang if !self.cur_token().is_on_new_line && self.is_ts => {
                     self.bump_any();
                     self.ast.expression_ts_non_null(self.end_span(lhs_span), lhs)
                 }
@@ -905,7 +905,7 @@ impl<'a> ParserImpl<'a> {
                 if self.source_type.is_jsx() {
                     return self.parse_jsx_expression();
                 }
-                if self.ts_enabled() {
+                if self.is_ts {
                     return self.parse_ts_type_assertion();
                 }
                 Err(self.unexpected())
@@ -951,13 +951,12 @@ impl<'a> ParserImpl<'a> {
         // Pratt Parsing Algorithm
         // <https://matklad.github.io/2020/04/13/simple-but-powerful-pratt-parsing.html>
         let mut lhs = lhs;
-        let is_ts = self.ts_enabled();
         loop {
             // re-lex for `>=` `>>` `>>>`
             // This is need for jsx `<div>=</div>` case
             let kind = self.re_lex_right_angle();
 
-            let Some(left_precedence) = kind_to_precedence(kind, is_ts) else { break };
+            let Some(left_precedence) = kind_to_precedence(kind, self.is_ts) else { break };
 
             let stop = if left_precedence.is_right_associative() {
                 left_precedence < min_precedence
@@ -976,7 +975,7 @@ impl<'a> ParserImpl<'a> {
                 break;
             }
 
-            if self.ts_enabled() && matches!(kind, Kind::As | Kind::Satisfies) {
+            if self.is_ts && matches!(kind, Kind::As | Kind::Satisfies) {
                 if self.cur_token().is_on_new_line {
                     break;
                 }
diff --git a/crates/oxc_parser/src/js/function.rs b/crates/oxc_parser/src/js/function.rs
index a5bb794897c43..e204053c46314 100644
--- a/crates/oxc_parser/src/js/function.rs
+++ b/crates/oxc_parser/src/js/function.rs
@@ -47,7 +47,7 @@ impl<'a> ParserImpl<'a> {
     ) -> Result<(Option<TSThisParameter<'a>>, Box<'a, FormalParameters<'a>>)> {
         let span = self.start_span();
         self.expect(Kind::LParen)?;
-        let this_param = if self.ts_enabled() && self.at(Kind::This) {
+        let this_param = if self.is_ts && self.at(Kind::This) {
             let param = self.parse_ts_this_parameter()?;
             if !self.at(Kind::RParen) {
                 self.expect(Kind::Comma)?;
@@ -135,7 +135,7 @@ impl<'a> ParserImpl<'a> {
         self.ctx =
             self.ctx.and_in(ctx.has_in()).and_await(ctx.has_await()).and_yield(ctx.has_yield());
 
-        if !self.ts_enabled() && body.is_none() {
+        if !self.is_ts && body.is_none() {
             return Err(self.unexpected());
         }
 
diff --git a/crates/oxc_parser/src/js/module.rs b/crates/oxc_parser/src/js/module.rs
index 088b4a424a818..82ada7b37b441 100644
--- a/crates/oxc_parser/src/js/module.rs
+++ b/crates/oxc_parser/src/js/module.rs
@@ -34,7 +34,7 @@ impl<'a> ParserImpl<'a> {
 
         self.bump_any(); // advance `import`
 
-        if self.ts_enabled()
+        if self.is_ts
             && ((self.cur_kind().is_binding_identifier() && self.peek_at(Kind::Eq))
                 || (self.at(Kind::Type)
                     && self.peek_kind().is_binding_identifier()
@@ -208,10 +208,10 @@ impl<'a> ParserImpl<'a> {
         self.bump_any(); // advance `export`
 
         let decl = match self.cur_kind() {
-            Kind::Eq if self.ts_enabled() => self
+            Kind::Eq if self.is_ts => self
                 .parse_ts_export_assignment_declaration(span)
                 .map(ModuleDeclaration::TSExportAssignment),
-            Kind::As if self.peek_at(Kind::Namespace) && self.ts_enabled() => self
+            Kind::As if self.peek_at(Kind::Namespace) && self.is_ts => self
                 .parse_ts_export_namespace()
                 .map(ModuleDeclaration::TSNamespaceExportDeclaration),
             Kind::Default => self
@@ -223,7 +223,7 @@ impl<'a> ParserImpl<'a> {
             Kind::LCurly => self
                 .parse_export_named_specifiers(span)
                 .map(ModuleDeclaration::ExportNamedDeclaration),
-            Kind::Type if self.peek_at(Kind::LCurly) && self.ts_enabled() => self
+            Kind::Type if self.peek_at(Kind::LCurly) && self.is_ts => self
                 .parse_export_named_specifiers(span)
                 .map(ModuleDeclaration::ExportNamedDeclaration),
             Kind::Type if self.peek_at(Kind::Star) => {
@@ -328,11 +328,8 @@ impl<'a> ParserImpl<'a> {
         // For tc39/proposal-decorators
         // For more information, please refer to <https://babeljs.io/docs/babel-plugin-proposal-decorators#decoratorsbeforeexport>
         self.eat_decorators()?;
-        let modifiers = if self.ts_enabled() {
-            self.eat_modifiers_before_declaration()?
-        } else {
-            Modifiers::empty()
-        };
+        let modifiers =
+            if self.is_ts { self.eat_modifiers_before_declaration()? } else { Modifiers::empty() };
 
         let declaration = self.parse_declaration(decl_span, &modifiers)?;
         let span = self.end_span(span);
@@ -362,16 +359,13 @@ impl<'a> ParserImpl<'a> {
             Kind::Class => self
                 .parse_class_declaration(decl_span, /* modifiers */ &Modifiers::empty())
                 .map(ExportDefaultDeclarationKind::ClassDeclaration)?,
-            _ if self.at(Kind::Abstract) && self.peek_at(Kind::Class) && self.ts_enabled() => {
+            _ if self.at(Kind::Abstract) && self.peek_at(Kind::Class) && self.is_ts => {
                 // eat the abstract modifier
                 let modifiers = self.eat_modifiers_before_declaration()?;
                 self.parse_class_declaration(decl_span, &modifiers)
                     .map(ExportDefaultDeclarationKind::ClassDeclaration)?
             }
-            _ if self.at(Kind::Interface)
-                && !self.peek_token().is_on_new_line
-                && self.ts_enabled() =>
-            {
+            _ if self.at(Kind::Interface) && !self.peek_token().is_on_new_line && self.is_ts => {
                 self.parse_ts_interface_declaration(decl_span, &Modifiers::empty()).map(|decl| {
                     match decl {
                         Declaration::TSInterfaceDeclaration(decl) => {
@@ -424,7 +418,7 @@ impl<'a> ParserImpl<'a> {
         let specifier_span = self.start_span();
         let peek_kind = self.peek_kind();
         let mut import_kind = ImportOrExportKind::Value;
-        if self.ts_enabled() && self.at(Kind::Type) {
+        if self.is_ts && self.at(Kind::Type) {
             if self.peek_at(Kind::As) {
                 if self.nth_at(2, Kind::As) {
                     if self.nth_kind(3).is_identifier_name() {
@@ -477,7 +471,7 @@ impl<'a> ParserImpl<'a> {
     }
 
     fn parse_import_or_export_kind(&mut self) -> ImportOrExportKind {
-        if !self.ts_enabled() {
+        if !self.is_ts {
             return ImportOrExportKind::Value;
         }
         // OK
@@ -521,7 +515,7 @@ impl<'a> ParserImpl<'a> {
         // export { type as as }       // name: `type`    type-export: `false` (aliased to `as`)
         // export { type as as as }    // name: `as`      type-export: `true`, aliased to `as`
         let mut export_kind = ImportOrExportKind::Value;
-        if self.ts_enabled() && self.at(Kind::Type) {
+        if self.is_ts && self.at(Kind::Type) {
             if self.peek_at(Kind::As) {
                 if self.nth_at(2, Kind::As) {
                     if self.nth_at(3, Kind::Str) || self.nth_kind(3).is_identifier_name() {
diff --git a/crates/oxc_parser/src/js/object.rs b/crates/oxc_parser/src/js/object.rs
index f6aaa6e608ac4..71976138f37e0 100644
--- a/crates/oxc_parser/src/js/object.rs
+++ b/crates/oxc_parser/src/js/object.rs
@@ -65,7 +65,7 @@ impl<'a> ParserImpl<'a> {
             // Report and handle illegal modifiers
             // e.g. const x = { public foo() {} }
             modifier_kind
-                if self.ts_enabled()
+                if self.is_ts
                     && modifier_kind.is_modifier_kind()
                     && peek_kind.is_identifier_or_keyword() =>
             {
diff --git a/crates/oxc_parser/src/js/statement.rs b/crates/oxc_parser/src/js/statement.rs
index da4edcee57722..4c9ceafa8cbcf 100644
--- a/crates/oxc_parser/src/js/statement.rs
+++ b/crates/oxc_parser/src/js/statement.rs
@@ -105,7 +105,7 @@ impl<'a> ParserImpl<'a> {
             // [+Return] ReturnStatement[?Yield, ?Await]
             Kind::Return => self.parse_return_statement(),
             Kind::Var => self.parse_variable_statement(stmt_ctx),
-            Kind::Const if !(self.ts_enabled() && self.is_at_enum_declaration()) => {
+            Kind::Const if !(self.is_ts && self.is_at_enum_declaration()) => {
                 self.parse_variable_statement(stmt_ctx)
             }
             Kind::Let if !self.cur_token().escaped() => self.parse_let(stmt_ctx),
@@ -116,7 +116,7 @@ impl<'a> ParserImpl<'a> {
             }
             Kind::Using if self.peek_kind().is_binding_identifier() => self.parse_using(),
             _ if self.at_function_with_async() => self.parse_function_declaration(stmt_ctx),
-            _ if self.ts_enabled() && self.at_start_of_ts_declaration() => {
+            _ if self.is_ts && self.at_start_of_ts_declaration() => {
                 self.parse_ts_declaration_statement(start_span)
             }
             _ => self.parse_expression_or_labeled_statement(),
diff --git a/crates/oxc_parser/src/jsx/mod.rs b/crates/oxc_parser/src/jsx/mod.rs
index 62cd1bccae1f5..6c06b45e88b91 100644
--- a/crates/oxc_parser/src/jsx/mod.rs
+++ b/crates/oxc_parser/src/jsx/mod.rs
@@ -95,8 +95,7 @@ impl<'a> ParserImpl<'a> {
         self.expect(Kind::LAngle)?;
         let name = self.parse_jsx_element_name()?;
         // <Component<TsType> for tsx
-        let type_parameters =
-            if self.ts_enabled() { self.try_parse_type_arguments()? } else { None };
+        let type_parameters = if self.is_ts { self.try_parse_type_arguments()? } else { None };
         let attributes = self.parse_jsx_attributes()?;
         let self_closing = self.eat(Kind::Slash);
         if !self_closing || in_jsx_child {
diff --git a/crates/oxc_parser/src/lib.rs b/crates/oxc_parser/src/lib.rs
index b7f0419dd3775..264771157cf76 100644
--- a/crates/oxc_parser/src/lib.rs
+++ b/crates/oxc_parser/src/lib.rs
@@ -356,8 +356,11 @@ struct ParserImpl<'a> {
     /// Parsing context
     ctx: Context,
 
-    /// Ast builder for creating AST spans
+    /// Ast builder for creating AST nodes
     ast: AstBuilder<'a>,
+
+    /// Precomputed typescript detection
+    is_ts: bool,
 }
 
 impl<'a> ParserImpl<'a> {
@@ -384,6 +387,7 @@ impl<'a> ParserImpl<'a> {
             state: ParserState::default(),
             ctx: Self::default_context(source_type, options),
             ast: AstBuilder::new(allocator),
+            is_ts: source_type.is_typescript(),
         }
     }
 
@@ -508,10 +512,6 @@ impl<'a> ParserImpl<'a> {
         self.errors.len() + self.lexer.errors.len()
     }
 
-    fn ts_enabled(&self) -> bool {
-        self.source_type.is_typescript()
-    }
-
     fn set_source_type_to_module_if_unambiguous(&mut self) {
         if self.source_type.is_unambiguous() {
             self.source_type = self.source_type.with_module(true);
diff --git a/crates/oxc_parser/src/ts/statement.rs b/crates/oxc_parser/src/ts/statement.rs
index ecf6a898ad4f5..6fb24353b15ba 100644
--- a/crates/oxc_parser/src/ts/statement.rs
+++ b/crates/oxc_parser/src/ts/statement.rs
@@ -116,7 +116,7 @@ impl<'a> ParserImpl<'a> {
     pub(crate) fn parse_ts_type_annotation(
         &mut self,
     ) -> Result<Option<Box<'a, TSTypeAnnotation<'a>>>> {
-        if !self.ts_enabled() {
+        if !self.is_ts {
             return Ok(None);
         }
         if !self.at(Kind::Colon) {
@@ -398,7 +398,7 @@ impl<'a> ParserImpl<'a> {
                 if declare {
                     self.parse_ts_declare_function(start_span, modifiers)
                         .map(Declaration::FunctionDeclaration)
-                } else if self.ts_enabled() {
+                } else if self.is_ts {
                     self.parse_ts_function_impl(start_span, FunctionKind::Declaration, modifiers)
                         .map(Declaration::FunctionDeclaration)
                 } else {
diff --git a/crates/oxc_parser/src/ts/types.rs b/crates/oxc_parser/src/ts/types.rs
index aa631c26c6b7b..8f09720c159c6 100644
--- a/crates/oxc_parser/src/ts/types.rs
+++ b/crates/oxc_parser/src/ts/types.rs
@@ -138,7 +138,7 @@ impl<'a> ParserImpl<'a> {
     pub(crate) fn parse_ts_type_parameters(
         &mut self,
     ) -> Result<Option<Box<'a, TSTypeParameterDeclaration<'a>>>> {
-        if !self.ts_enabled() {
+        if !self.is_ts {
             return Ok(None);
         }
         if !self.at(Kind::LAngle) {
@@ -811,7 +811,7 @@ impl<'a> ParserImpl<'a> {
     pub(crate) fn parse_type_arguments_in_expression(
         &mut self,
     ) -> Result<Option<Box<'a, TSTypeParameterInstantiation<'a>>>> {
-        if !self.ts_enabled() {
+        if !self.is_ts {
             return Ok(None);
         }
         let span = self.start_span();
@@ -1049,7 +1049,7 @@ impl<'a> ParserImpl<'a> {
         kind: Kind,
         is_type: bool,
     ) -> Result<Option<Box<'a, TSTypeAnnotation<'a>>>> {
-        if !self.ts_enabled() {
+        if !self.is_ts {
             return Ok(None);
         }
         if !self.at(Kind::Colon) {
@@ -1315,7 +1315,7 @@ impl<'a> ParserImpl<'a> {
         &mut self,
         is_constructor_parameter: bool,
     ) -> Modifiers<'a> {
-        if !self.ts_enabled() {
+        if !self.is_ts {
             return Modifiers::empty();
         }