The Tool Desk
Outbyte PC Repair FREERepair Windows errors before they cause bigger problemsFix Now →Outbyte Driver Updater FREEScan for outdated or missing drivers - takes under a minuteDriver Scan →Use Chrome DevTools’ Network panel to simulate a slower connection for a web page without changing your Windows computer’s actual internet service. Choose a built-in throttling preset, create a custom profile for specific speeds and latency, or select Offline to test the no-connection case.
Use a preset to simulate a slower connection
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Open the website you want to test in Chrome, then open DevTools. Select the Network panel.
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In the Network panel, open the throttling menu, which usually shows No throttling, and choose a slower preset. Chrome documents choices including Fast 4G, Slow 4G and 3G; the separate Network Conditions controls also document Fast 3G, Slow 3G and Offline. Chrome DevTools: Network panel
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Reload the page and observe how it loads. The chosen emulation applies to page testing in DevTools; it does not slow the Windows computer’s connection for other apps. Chrome DevTools: Network panel
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Preset names are useful for a quick check, but record the exact preset when comparing runs. A result can also depend on cache state and whether CPU throttling is enabled.
Open Network Conditions from another DevTools panel
If you want the network controls available while viewing a different DevTools panel, open the Command Menu with Control+Shift+P on Windows, search for Network Conditions, and select it. You can also use the throttling controls in the Network panel itself. Chrome DevTools: Network conditions
Set a custom download speed, upload speed and latency
Use a custom profile when a preset does not represent the connection you need to test. In DevTools settings, create a network throttling profile, give it a recognizable name, and enter its download speed, upload speed in Kbps and latency in milliseconds. The documented profile controls also include packet-related parameters. Save the profile, then select it from the Network panel’s throttling menu. Chrome DevTools: Network panel
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There is no single universal definition of a “slow” connection. For repeatable tests, write down the custom profile’s actual values rather than describing it only as slow.
Choose the right test condition
| Option | Use it for | What to note |
|---|---|---|
| Built-in preset | A quick test of general page behavior under a slower network condition. | Record the selected preset and cache setting. Presets are documented in Chrome’s Network panel and Network conditions references. |
| Custom profile | A test that needs specified download and upload rates, latency, or packet parameters. | Record the profile name and the values entered. Chrome DevTools: Network panel |
| Offline | Checking how a page behaves with no simulated network connection. | Offline is a distinct condition, not an especially slow connection. Chrome DevTools: Network panel |
Control cache when testing first visits
Cached files can make a repeat visit appear faster than a first visit. To reduce that effect, enable Disable cache in the Network panel while DevTools is open, or use Empty Cache and Hard Reload from the reload options with DevTools open. Chrome DevTools: Network panel Chrome DevTools: Network conditions
Choose the cache behavior that matches the question you are testing: a cold visit without stored files or a repeat visit that may benefit from cache. Keep the setting the same across runs you intend to compare.
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Keep network throttling separate from CPU throttling
For a network-only test, set conditions in the Network panel. Device Mode’s Mid-tier mobile and Low-end mobile presets combine network and CPU limits: Chrome documents Mid-tier as fast 3G plus a four-times CPU slowdown, and Low-end as slow 3G plus a six-times CPU slowdown. CPU slowdown is relative to the normal capability of the computer running the test. These combined presets therefore test more than network speed alone. Chrome DevTools: Device Mode
Apply conditions to selected requests (Chrome 145 and later)
Chrome’s documentation says individual request throttling starts with Chrome 145. It can attach conditions to selected requests or URL patterns, which is useful when only particular resources should be affected. Check your Chrome version and confirm the option is available in DevTools before relying on it. When rules overlap, Chrome applies matching rules in order, with the first matching rule taking precedence. Chrome for Developers: Throttle individual network requests
Independent reader supportYour contribution helps us test, update, and keep practical guides available for everyone.Make test results repeatable
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Record the preset name or the custom profile’s download, upload and latency values.
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Record whether cache was disabled or cleared, and whether CPU throttling was enabled.
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Use the same page state and reload method when comparing runs.
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Check for DevTools’ warning icon when throttling or Offline simulation is active, so you do not mistake an emulated condition for an ordinary run. Chrome DevTools: Network panel
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