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Optimize Performance Under Varying Network Conditions

It’s easy to overlook the network conditions your users will face on mobile. Use DevTools to emulate different network conditions. Fix any load time issues and your users will thank you.


  • Without affecting traffic to other tabs, evaluate your site''s performance using the Chrome DevTools network emulator.
  • Use custom profiles that are specific to your audiences network conditions.

Emulate network connectivity

Network conditioning allows you to test your site on a variety of network connections, including Edge, 3G, and even offline. It throttles the maximum download and upload throughput (rate of data transfer). Latency manipulation enforces a minimum delay in connection round-trip time (RTT).

Network Conditioning is turned on through the Network panel. Select a connection from the dropdown to apply network throttling and latency manipulation.

Select Network Throttle

Tip: You can also set network throttles via the Network conditions drawer.

When a Throttle is enabled the panel indicator will show a warning icon. This is to remind you that throttling is enabled when you are in other panels.

Network Panel Selector With Warning Indicator

Custom throttles

DevTools provides a solid foundation of default conditions. You may need to add custom conditions to cover your audiences primary conditions.

To add a condition open the dropdown to apply a condition. Under the custom header find and select the Add... option. This will open the DevTools settings dialog with the "Throttling" tab open.

Throttle Settings Index

First, click the Add custom profile button. This opens an inline form to supply the profiles conditions. Accurately fill the form out then press the Add button when it meets your needs.

Throttle Settings Add Custom Throttle

You may modify an existing custom profile by hovering the entry. On hover the Edit and Delete icons are shown to the right of the entry.

Throttle Settings Modify Custom Entry

Now you may close the settings dialog. Your new custom profiles will be shown under the custom header to select a condition.

Open the network conditions drawer

You can access network functions while other DevTools panels are open with the Network conditions drawer.

the network conditions drawer

Access the drawer from the DevTools main menu (Main Menu > More Tools > Network Conditions).

opening the network conditions drawer


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