Get your PD in seconds with your webcam or a photo — accurate, private, and free. Everything runs in your browser, so your face never leaves your device.
100% private No uploads Instant result No sign-up
Private by design. Face detection and every calculation happen on your device. No image or video is uploaded, and nothing is stored.
Advertisement
Most people don’t need this — the webcam method is easier and more reliable.
Look at the camera — nothing to hold, nothing to aim. It measures automatically. Everything stays on your device.
Here’s what will happen:
Sit about an arm’s length away, with light on your face.
Look at the camera and keep your head straight and level.
Hold still — it captures on its own. You don’t have to click anything.
Tip: good, even lighting and a plain background help. You don’t need a card here — this uses your iris as the ruler.
Your result
Run a measurement and your pupillary distance will appear here.
What is pupillary distance?
Pupillary distance (PD) is the distance between the centers of your two pupils, measured in millimeters. It tells an optician where to place the optical center of each lens so you look through the correct part of your glasses. Getting it right keeps your vision sharp and comfortable; getting it wrong can cause eye strain, headaches, or blur — especially in stronger prescriptions.
A typical adult PD ranges from about 54 to 74 mm, averaging around 63 mm. PD can be written as a single binocular number (e.g. 63) or as two monocular numbers measured from the bridge of your nose to each pupil (e.g. 31.5/31.5).
How to measure your PD
Pick a mode above — Webcam for a live reading, Photo to upload an image, or Card for the highest accuracy.
Sit about 40–60 cm (16–24 in) from the camera in good, even lighting.
Look straight at the lens, keep your head level, and hold still.
In Webcam mode, just hold still — it captures automatically with a short countdown (or press Measure now). It takes the median of ~30 frames.
Read your binocular PD, plus monocular and near values if you need them.
For the most precise result, use Card mode: hold any standard-size card (any ISO/IEC 7810 card — no credit card needed) in the same plane as your eyes and drag the on-screen markers to its edge to calibrate the scale. It works live with your webcam or from an uploaded photo.
Advertisement
How accurate is this tool?
The tool finds 478 facial landmarks (including the iris) and uses a known real-world length as a ruler: either the average iris diameter (~11.7 mm) or, in Card mode, a standard ISO/IEC 7810 card (85.60 mm). In Webcam mode it captures multiple frames and takes the median for stability, and it shows a confidence score based on how steady and well-aligned your head was.
Under good conditions, results are usually within 1–2 mm. Accuracy depends on lighting, image sharpness, and head pose — facing the camera squarely with a level head matters most. Card mode is the most accurate because the reference length is larger and unaffected by eye anatomy.
Frequently asked questions
Is my video or photo uploaded anywhere?
No. All face detection and the entire calculation run locally in your browser using on-device AI. No image, video, or measurement is ever sent to a server or stored.
What is a normal pupillary distance?
Most adults fall between 54 and 74 mm. The average is roughly 63 mm for men and 61 mm for women. Children are typically smaller, around 41 to 55 mm.
What is the difference between single (binocular) and dual (monocular) PD?
Binocular PD is the total distance between the centers of both pupils. Monocular PD is measured from the center of your nose to each pupil separately (for example 31.5/31.5), which matters when your eyes are not perfectly symmetric.
What is near PD?
Near PD is used for reading glasses. Because your eyes converge when focusing up close, near PD is about 3 mm smaller than your distance PD.
Can I measure my PD on a phone?
Yes. The webcam and photo modes work in mobile browsers. Use good, even lighting, hold the phone at eye level, look straight ahead, and keep still.
How accurate is it for ordering glasses?
Under good conditions the result is typically within 1 to 2 mm, which is fine for most single-vision glasses. For high prescriptions, prism, or progressive lenses, confirm with an optician — and use Card mode for the best accuracy.
Note: this tool provides an estimate and does not replace a professional eye exam. For high-power, progressive, or prism lenses, confirm your PD with an optometrist or ophthalmologist before ordering.