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Caffeine Chrome extension

Caffeine stops your computer from dimming the screen or going to sleep, at either display or full-system level, with a timer or download-aware option. It's best for anyone doing presentations, downloads, or reading long content without touching the mouse. The catch: it overrides your OS power settings while active, so battery use goes up.

  • PriceFree
  • CategoryProductivity
  • Works inChrome, Edge, Brave (desktop)

Last checked against the Chrome Web Store listing · Independent, not affiliated with Google

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Pros

  • simple one-click toggle from the toolbar button
  • two operation levels: display only or full system
  • can auto-release after a chosen time, from 5 minutes to 24 hours
  • can keep the system awake specifically until a download finishes
  • does nothing to power settings when disabled

Cons

  • keeps the screen or system on, which increases power and battery use while active
  • behavior on lid-close varies by operating system and hardware
  • no per-site or per-tab rules; it's a global keep-awake toggle

Best for

  • keeping the screen on during presentations or reading
  • preventing sleep during long downloads
  • avoiding manual changes to system power settings
  • temporarily overriding sleep for a set period, like 30 minutes or a few hours

Skip it if

  • users who want to save battery on a laptop while away from the charger
  • anyone who needs the system to sleep automatically for security reasons

Key features

  • toolbar button to toggle keep-awake on or off
  • display-level mode that only stops screen dimming
  • system-level mode that prevents full sleep or hibernation
  • timed keep-awake from 5 minutes up to 24 hours
  • keep-awake-until-download-completes mode
  • right-click context menu to change the operation level

What Caffeine does

Caffeine prevents your screen from dimming or your system from sleeping by overriding power-saving settings while it's active. It offers a display-level mode that stops monitors from dimming or showing a screensaver, and a system-level mode that keeps the entire machine from entering a power-saving state, useful for presentations, reading, or unattended downloads.

Timed and download-aware modes

Instead of leaving the system awake indefinitely, you can set Caffeine to keep things active for a specific period, from 5 minutes to 24 hours, after which it releases automatically. There's also a mode that keeps the system awake only until a file finishes downloading, then lets it return to its default sleep behavior.

Is Caffeine safe?

Caffeine works locally by adjusting the browser's power-management API and doesn't need access to page content or personal data to function. When disabled, it doesn't alter your computer's power settings at all; it only overrides them while the toggle is active, and stops overriding them the moment you turn it off.

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Caffeine: FAQs

Is Caffeine free?

Yes, Caffeine is free to install and use, including both the display and system-level keep-awake modes.

Is Caffeine safe to use?

Yes, it only adjusts power-management behavior while active and doesn't access page content or personal data.

How do I use Caffeine?

Install it, pin the icon, and click it once to keep your screen or system awake; click again to release it.

What's the difference between display and system mode?

Display mode only stops the screen from dimming; system mode also prevents the whole machine from sleeping or hibernating.

Does Caffeine drain the battery faster?

Yes, keeping the screen or system awake uses more power than letting it sleep normally, so expect faster battery drain while active.

Does Caffeine work when my laptop lid is closed?

It depends on your operating system and hardware; some systems allow background activity with the lid closed, others suspend everything.

Can Caffeine turn off automatically after a set time?

Yes, you can set it to keep the system awake for a chosen duration, from 5 minutes to 24 hours, then release automatically.

Does Caffeine keep the system awake during downloads?

Yes, there's a mode specifically for staying awake until an active download completes.

What are alternatives to Caffeine?

Other keep-awake extensions or your operating system's built-in power settings can achieve a similar effect.

Does Caffeine change my computer's power settings permanently?

No, it only overrides sleep behavior while toggled on and restores default power settings once you turn it off.