Set the JavaScript mode for an application

task brazil Updated Sep 10, 2026 1 min read set-javascript-mode-application.md

Configure which ECMAScript features can be used in an application by selecting the JavaScript mode.

Before you begin

Role required: delegated developer role granting full access or admin

About this task

The JavaScript mode is a design and runtime setting for custom applications and scripts. To support existing server-side scripts and new scripts developed to the ECMAScript 2021 standard, the JavaScript engine has three modes: ECMAScript 2021 (ES12), ES5 Standards, and Compatibility. For more information about each mode, see JavaScript modes.

For applications that use ES5 Standards or Compatibility mode, you can also turn on ECMAScript 2021 (ES12) for individual scripts in the application. For more information, see Turn on ECMAScript 2021 (ES12) mode for a script.

Note: Switching the JavaScript mode to ECMAScript 2021 (ES12) for an existing application might change the behavior of its scripts. For more information, see Considerations for switching JavaScript modes.

Procedure

In the application navigator, enter sys_app.list.
Select an application.
In the JavaScript Mode field, select the mode to use.
- ECMAScript 2021 (ES12): Supports a subset of ECMAScript 2021 (ES12) and ECMAScript 2022 (ES13) syntax and features.
- ES5 Standards Mode: Supports ECMAScript5 syntax and features.
- Compatibility Mode: Used for all scripts developed prior to the addition of ES5 Standards mode.
Select Update.

Parent Topic:JavaScript modes

52 lines · 2.8 KB Wrap lines

---
title: Set the JavaScript mode for an application
description: Configure which ECMAScript features can be used in an application by selecting the JavaScript mode.
locale: en-US
canonical_url: https://www.servicenow.com/docs/r/api-reference/scripts/set-javascript-mode-application.html
release: brazil
product: Scripts
classification: scripts
topic_type: task
last_updated: "2026-09-10"
reading_time_minutes: 1
breadcrumb: [JavaScript modes, JavaScript engine, Write server-side scripts, Scripting, API implementation, API implementation and reference]
---

# Set the JavaScript mode for an application

Configure which ECMAScript features can be used in an application by selecting the JavaScript mode.

## Before you begin

Role required: delegated developer role granting full access or admin

## About this task

The JavaScript mode is a design and runtime setting for custom applications and scripts. To support existing server-side scripts and new scripts developed to the ECMAScript 2021 standard, the JavaScript engine has three modes: ECMAScript 2021 \(ES12\), ES5 Standards, and Compatibility. For more information about each mode, see [JavaScript modes](https://raw.githubusercontent.com/ServiceNow/ServiceNowDocs/brazil/markdown/api-reference/scripts/c_JS_modes.md).

For applications that use ES5 Standards or Compatibility mode, you can also turn on ECMAScript 2021 \(ES12\) for individual scripts in the application. For more information, see [Turn on ECMAScript 2021 \(ES12\) mode for a script](https://raw.githubusercontent.com/ServiceNow/ServiceNowDocs/brazil/markdown/api-reference/scripts/set-es12-mode-scripts.md).

**Note:** Switching the JavaScript mode to ECMAScript 2021 \(ES12\) for an existing application might change the behavior of its scripts. For more information, see [Considerations for switching JavaScript modes](https://raw.githubusercontent.com/ServiceNow/ServiceNowDocs/brazil/markdown/api-reference/scripts/considerations-switching-javascript-mode.md).

## Procedure

1. In the application navigator, enter `sys_app.list`.

2. Select an application.

3. In the **JavaScript Mode** field, select the mode to use.

- ECMAScript 2021 \(ES12\): Supports a subset of ECMAScript 2021 \(ES12\) and ECMAScript 2022 \(ES13\) syntax and features.
- ES5 Standards Mode: Supports ECMAScript5 syntax and features.
- Compatibility Mode: Used for all scripts developed prior to the addition of ES5 Standards mode.
4. Select **Update**.

**Parent Topic:**[JavaScript modes](https://raw.githubusercontent.com/ServiceNow/ServiceNowDocs/brazil/markdown/api-reference/scripts/c_JS_modes.md)

**Related topics**

[Modify an app's settings in ServiceNow Studio](https://raw.githubusercontent.com/ServiceNow/ServiceNowDocs/brazil/markdown/application-development/modify-an-apps-settings-in-servicenow-studio.md)