CalcWolf Health 20-20-20 Eye Strain Relief Timer Calculator
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20-20-20 Rule Eye Strain Calculator

Personalized break schedule for your screen hours.

📅 Updated April 2026 Formula verified 📖 4 min read 🆓 Free · No sign-up

The 20-20-20 rule

Every 20 minutes, look at something 20 feet away for 20 seconds. This relaxes the ciliary muscle in your eye that contracts while focusing on a screen, reducing digital eye strain (asthenopia).

Signs of digital eye strain

  • Dry, itchy, or burning eyes
  • Headaches (especially behind the eyes)
  • Blurry vision after screen use
  • Neck and shoulder tension (related to screen position)
Frequently asked questions
Does the 20-20-20 rule actually work?
Yes — research shows it significantly reduces eye strain symptoms. Set a timer app or use tools like Time Out (macOS) or EyeLeo to automate it.
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