How to Activate the iPhone Debug Console or Web Inspector

Use Safari's web developer tools to study problematic websites

Before iOS 6, the iPhone's Safari web browser had a built-in Debug Console that developers used to find web page defects. Recent versions of iOS use Web Inspector instead. Web Inspector is used by web developers to modify, debug, and optimize websites on Macs and iOS devices.

To use Web Inspector, connect your iPhone to your Mac computer with a cable, open the Mac's Safari, then enable the ​Develop menu in the Safari Advanced Preferences.

Information in this article applies to iPhones and other iOS devices with iOS 6 through iOS 12 and Macs on Mac OS X Leopard (10.5) and later unless otherwise noted.

Person holding an iPhone and a can of bug repellant
Miguel Co / Lifewire 

Activate Web Inspector on iPhone iOS 6 and Later

The Web Inspector is disabled by default since most iPhone users have no use for it. However, developers can activate it in a few short steps. Here's how:

  1. Tap the Settings icon on the iPhone Home screen.

    On an iPhone with an early version of iOS, access the Debug Console through Settings > Safari > Developer > Debug Console. Whenever Safari on the iPhone detects CSS, HTML, and JavaScript errors, details of each are displayed in the debugger.

  2. Scroll down and tap Safari to open the screen that contains everything related to the Safari web browser on your iPhone, iPad, or iPod touch.

  3. Scroll to the bottom of the screen and tap Advanced.

  4. Move the Web Inspector toggle switch to the On position.

    Screenshots of an iPhone showing how to turn on Safari's Web Inspector

Connect iPhone to Safari on a Mac

To use the Web Inspector, connect your iPhone or another iOS device to a Mac that's running the Safari web browser. Plug your device into the computer using a cable.

With Safari open, do the following:

  1. Click Safari in the menu bar and choose Preferences.

    A screenshot of Safari with the Preferences menu item highlighted
  2. Click the Advanced tab.

    A screenshot of Safari preferences with the Advanced tab highlighted
  3. Select the Show Develop menu in menu bar check box.

    A screenshot of Safari advanced settings with the "Show Develop Menu" option highlighted
  4. Exit the settings window.

  5. In the Safari menu bar, click Develop, then select Connect Web Inspector.

    A screenshot of Safari with "Connect Web Inspector" under the Develop menu highlighted

Your attached iPhone or other iOS device appears in the Develop drop-down menu. With Web Inspector open, developers can inspect all the resources on a web page. The Web Inspector window contains editable HTML and notes regarding the styles and layers of the web page in a separate panel.

With Safari 9 and OS X Mavericks (10.9), Apple introduced Responsive Design Mode in Web Inspector. Developers use this built-in simulator to preview how web pages scale to different screen sizes, resolutions, and orientations.