PupilCheck

Clinical Pupil Assessment Tool
Detecting pupil...

Pupil Size Comparison

Compare left and right pupil sizes to detect anisocoria. Uses the patient's own iris as an internal reference for distance-independent, ratio-based comparison.

How to Use

  1. Choose "Both Eyes" for a single landscape photo, or "Single Eye" for sequential close-ups
  2. Frame both eyes (or one eye) so the iris is fully visible
  3. Verify and adjust the auto-detected pupil and iris circles
  4. Review side-by-side comparison and clinical assessment
Clinical Tip: Hold the phone 10-15 cm from the eye. Ensure the entire iris is visible in the frame. The iris is used as an internal ruler, so exact camera distance does not matter. Use the torch for standardized lighting and reactivity testing.
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Left Eye (OS)
Left Eye (OS)
Pupil/Iris ratio -
Pupil diameter (px) -
Iris diameter (px) -
Est. pupil size (~11.7 mm iris) -
Both Eyes
Right (OD)
Left (OS)
Tap an eye to adjust
Right (OD) - -
Left (OS) - -

Light Stimulus

Apply a light stimulus to the patient's eyes to test pupil reactivity.

Phone torch

Torch will activate. Hold phone 20-30 cm from the face to avoid blinding the patient.

Penlight (recommended)

Shine a penlight from the side into both eyes. This is the standard clinical technique.

Keep the light on while you capture. Maintain the same distance as the first photo.

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Pupil/Iris ratio difference
Left Eye (OS)
- ratio
-
Right Eye (OD)
- ratio
-

Clinical Considerations

Disclaimer: This tool provides ratio-based pupil comparison for clinical screening purposes only. It is not a certified medical device. Accuracy depends on image quality, lighting, and correct circle placement. Always correlate with full clinical assessment. The pupil-to-iris ratio comparison is distance-independent. Approximate mm values use 11.7 mm average iris diameter (individual range ~10.2-13.0 mm). Where supported, camera focus distance is used as a consistency check between captures.