What Is the 20-20-20 Rule for Digital Eye Strain?
The 20-20-20 rule is a simple screen-break reminder: every 20 minutes, look at something about 20 feet away for at least 20 seconds. It may help interrupt prolonged near-focus and remind you to blink, but it is not a treatment for persistent eye pain or vision changes.
What to remember.
Use the rule as a recurring break cue, not a medical treatment.
Looking across a room is a practical substitute when 20 feet is hard to measure.
Persistent pain, headaches, double vision, or vision changes warrant professional advice.
The useful detail.
How to use the 20-20-20 rule
Set a quiet reminder for every 20 minutes of screen work. When it appears, stop reading, relax your gaze, and look toward a distant object for at least 20 seconds. The useful behavior is breaking continuous close focus; exact distance measurement is less important than choosing a genuinely distant target.
What the rule does not prove
The rule is widely recommended as a low-risk habit, but the exact 20-minute and 20-second intervals are not a guarantee against digital eye strain. Screen comfort also depends on lighting, glare, text size, viewing distance, blinking, corrective lenses, and underlying eye conditions.
How Sanctuary supports it
Sanctuary can pair focus periods with eye-break cues and a short breathing reset. The cue is optional and designed to help you remember the habit; it does not diagnose, prevent, or treat an eye condition.
Direct answers.
Does the 20-20-20 rule prevent eye damage?
It is a comfort and break-taking habit, not proof of prevention and not a substitute for eye care.
What if I cannot see something 20 feet away?
Look toward the farthest comfortable point in the room or out a window and let your near-focus relax.
Read the evidence.
American Optometric Association: Computer vision syndrome
Clinical overview of digital eye strain, symptoms, and viewing habits.
A calmer cue, when you want it.
Use Sanctuary for configurable focus periods, eye-break reminders, guided breathing, and optional sound—without treating a wellness tool as medical care.