Screen Distance

Measure your real eye-to-screen distance

Why someone would use it

An eye exam measures how you read letters across the room. Computer glasses are for a different distance: the monitor you sit at for hours. If that working distance is never measured, the prescription is a guess. Patients who sit far from the screen often leave with glasses that do not feel right. They want the pair that matches how they actually work, not only how they read a chart on the wall.

Doctors want to give a quality prescription they can stand behind. They can dial the lens to a real number when the patient arrives with one. Screen Distance measures eye-to-screen distance in the browser. The reading is accurate within 3 cm. Face detection runs for about seven seconds. Nothing is uploaded.

The case

Callbacks cost the practice. The first visit is what gets billed. When computer glasses come back “off,” that follow-up does not pay, and a frustrated patient may not return. The usual miss is simple: the exam never captured how far they sit from the screen — 30 inches and more is common, and it is not the same as the letter chart.

Patients measure at home, on the computer they actually use. They bring a number the doctor can use: average distance, a range, and how much time was too close or too far. The doctor dials the prescription to that working distance. Fewer callbacks. A pair that matches the desk, not only the exam room.

How it works

Open the tool on a desktop or laptop at your computer. Calibrate, look at the screen, and get a result in under a minute. Phone users can enter an estimated distance in manual mode. All processing stays on the device. Share the result with the office before the visit. It is an estimate, not medical advice, and it is not a substitute for the exam — it is the missing measurement the exam room usually skips.