The appearance of the eyes depends mainly on the shape of the eyelid opening, their inclination, their spacing, the position of the eyelids and their depth in the orbit.
To carry out the measurements correctly, you must use a strictly frontal photograph, looking straight ahead and your head in a neutral position. The device must be placed at eye level and far enough away to limit wide-angle distortion. For depth measurements, a strict profile photograph is necessary.
1. The general shape of the eye
a. Length of eyelid opening
The visible length of the eye is called palpebral fissure length or PFL. It corresponds to the distance between the medial canthus, that is to say the inner corner of the eye, and the lateral canthus, the outer corner.
In anthropometry, these two points are called endocanthion and exocanthion.
You must measure in a straight line:
medial canthus → lateral canthus
In young men, average measurements vary depending on the population, but are generally around 27 to 31 mm. In a study of Caucasian male faces considered attractive, the average length was 27.3 mm.
The absolute value, however, remains less interesting than the length of the eye in relation to the face.
The ratio is:
PFL ÷ bizygomatic width × 100
Bizygomatic width corresponds to the distance between the two most lateral points of the cheekbones.
An area of around 19.5 to 21.5% is a good benchmark. In the previously cited sample of attractive male faces, the ratio was approximately 19.6%.
An eye representing approximately 20% of the total width of the face therefore constitutes a useful central value.
A low value produces small eye openings relative to the face. A higher value produces horizontally longer eyes.
b. Height of the eyelid opening
The height is called palpebral fissure height or PFH.
It is measured vertically at the level of the pupil, between the edge of the upper eyelid and that of the lower eyelid.
It is necessary to measure:
upper eyelid → lower eyelid
In young adult men, several studies find approximately 9 to 11 mm.
A greater height gives a more open and rounder eye. A lower height gives a narrower opening vertically.
This measurement should above all be compared to the length of the eye.
c. Eye Aspect Ratio
The Eye Aspect Ratio describes how horizontally the opening of the eye is elongated.
It is calculated as follows:
PFL ÷ PFH
With an eye 30mm long and 10mm high:
30 ÷ 10 = 3
An area around 2.9 to 3.5 is a good benchmark.
Around 3.1 to 3.3, the eye has a fairly horizontal appearance while maintaining a normal height.
Below about 2.7 to 2.8, the aperture becomes relatively round. Conversely, a very high ratio produces a particularly narrow aperture.
2. The tilt and corners of the eyes
a. Canthal tilt
The canthal tilt corresponds to the angle formed by the line connecting the inner corner to the outer corner of the eye in relation to the horizontal.
We trace:
medial canthus → lateral canthus
The result can be negative, neutral or positive.
Negative canthal tilt: the lateral canthus is lower than the medial canthus.
Canthal tilt zero, around 0°: the two corners are approximately at the same height.
Positive canthal tilt: the lateral canthus is higher than the medial canthus.
In humans, we can approximately retain:
less than 0°: negative
0°: horizontal
+3 to +5°: slightly positive
+5 to +8.5°: marked but moderate positive inclination
more than +10°: significant inclination
A study of Caucasian men selected in particular from modeling and cinema found an average canthal tilt of 6.51° ± 2.67°.
A slightly positive tilt contributes to a more upward and angular shape. A negative inclination, on the contrary, gives a downward direction to the eye.
b. Medial canthus
The medial canthus is the inner corner located near the nose.
It can be relatively rounded or longer and pointed. A horizontally elongated inner corner increases the apparent length of the eye without increasing its height.
It may also have a slight downward orientation before the lower eyelid rises outwards, which contributes to the almond shape.
A medial canthal angle can be measured by placing the vertex of the angle at the inner corner and following the directions of the upper and lower eyelids. Some classifications use approximately 20 to 42°, but this measurement is less reproducible than canthal tilt.
The general shape of the internal corner therefore often remains more useful to observe directly.
c. Lateral canthus
The lateral canthus corresponds to the outer corner of the eye.
Its height relative to the medial canthus directly determines the canthal tilt.
In an almond shape, it usually forms a fairly sharp end. A very rounded external corner, on the contrary, increases the impression of roundness of the eyelid opening.
3. Eye spacing and size
a. Interpupillary distance
The interpupillary distance or IPD corresponds to the distance between the center of the two pupils when the gaze is directed straight ahead.
In adult men, it is generally around 60 to 70 mm, often around 63 to 65 mm.
To know if the eyes are close together or apart, you must however compare this measurement to the width of the face.
The Eye Separation Ratio is calculated as follows:
IPD ÷ bizygomatic width
An area around 0.45 to 0.47 is a good benchmark.
In a sample of attractive male faces, the average IPD was 63.8 mm for a bizygomatic width of 139 mm, or approximately 0.459.
We can therefore retain approximately 0.46 as the central value.
Below 0.44 to 0.45, the eyes become relatively close together. Above 0.47 to 0.48, they become relatively apart.
b. Intercanthal distance
The intercanthal distance or ICD corresponds to the space between the two inner corners of the eyes.
It is measured as follows:
left medial canthus → right medial canthus
It is generally around 30 to 35 mm in adults.
To interpret it, we compare it to the length of an eye:
ICD ÷ PFL
A value close to 1 means that the space between the eyes is approximately the length of one eye.
An area around 0.92 to 1.05 is a good benchmark.
Above 1, the space between the eyes is greater than the length of an eye. Below 1, it is smaller.
This measure does not replace the IPD. Two people can have the same interpupillary distance but different intercanthal spacings if their eyes are not the same length.
c. Distance between external canthi
The outer-canthal distance or OCD corresponds to the total width occupied by the two eyes and the space between them.
It is measured as follows:
left lateral canthus → right lateral canthus
It can then be compared to the width of the face:
OCD ÷ bizygomatic width
An area around 0.62 to 0.68 is a good benchmark, with around 0.65 as the central value.
A high value means that the eye region takes up a large portion of the width of the face. A low value means it is relatively compact.
4. The eyelids and exposure of the eye
a. Upper eyelid
Upper Eyelid Exposure or UEE corresponds to the amount of upper eyelid visible.
It is measured at the level of the pupil between the upper edge of the eyelashes and the visible crease of the eyelid.
A lower exposure produces a more compact aperture.
Around 0 to 4 mm is a useful order of magnitude.
Around 2 to 4 mm, a small strip of eyelid remains visible. Close to 0 mm, the eyelid is heavily hooded.
Large exposure visually increases the height of the entire eye region.
b. Hoodie
Hooding corresponds to the covering of part of the upper eyelid by the tissues located above.
It depends in particular on the shape of the supra-orbital rim, the position of the eyebrow, the fat of the upper eyelid and the skin.
Moderate hooding reduces exposure of the upper eyelid and accentuates the horizontal aspect of the eye.
A very large hooding can, on the contrary, completely hide the fold or weigh down the opening.
c. Upper eyelid position
The position of the upper eyelid can be measured with the MRD1.
We use the light reflection located in the center of the cornea as a reference point and measure to the edge of the upper eyelid.
A normal value is approximately around 3.5 to 5 mm.
The upper eyelid normally slightly covers the top of the cornea.
If it rises further, the eye appears more open vertically. If it goes down a lot, the opening becomes smaller.
5. The lower eyelid and under the eye
a. Lower eyelid position
The position of the lower eyelid can be measured with the MRD2.
We measure from the central reflection of the cornea to the edge of the lower eyelid.
A usual anatomical value is around 4 to 5.5 mm.
The lower eyelid is normally located approximately at the lower edge of the cornea.
b. Scleral show
The scleral show corresponds to the white band visible between the lower edge of the iris or cornea and the lower eyelid.
We measure:
lower edge of the cornea → edge of the lower eyelid
When the eyelid meets the lower edge of the cornea:
scleral show = 0 mm
A value of 1 mm means that a white band of approximately 1 mm is visible under the cornea.
A value close to 0 mm is the main benchmark sought. In a study of male and female faces considered attractive, none of the subjects had lower scleral show.
The more this exposure increases, the more the eye appears vertically open.
c. Infra-orbital support
The shape of the lower eyelid also depends on the infra-orbital rim and the cheekbone.
A sufficiently projected rim further supports the eyelid and limits the impression of a globe coming out of its orbit.
Conversely, a recessed infra-orbital region can accentuate the hollows under the eyes, the exposure of the globe and the scleral show.
6. Eye depth
a. Deep eyes and prominent eyes
A deep-set eye appears located deeper in its socket.
The supraorbital rim protrudes more above the globe and the infraorbital region better supports its lower part.
Conversely, a prominent eye protrudes more beyond the bony frame.
This apparent depth does not depend solely on the globe itself. It also depends on the brow ridge, cheekbones, infra-orbital rim and the root of the nose.
b. Orbital vector
The orbital vector compares the projection of the eye with that of the infra-orbital rim.
On a strict profile, we compare the most advanced point of the cornea to the infra-orbital rim.
When the infra-orbital rim is further forward, the vector is positive.
When the two are approximately aligned, it is neutral.
When the cornea protrudes further forward, the vector is negative.
We can remember:
orbital vector > 0°: positive
orbital vector ≈ 0°: neutral
orbital vector < 0°: negative
A study on healthy subjects found an average of around +11.7°. A value around +10° therefore constitutes a good anatomical order of magnitude.
A negative vector is associated with a greater projection of the globe relative to the infra-orbital rim and more scleral show.
c. Globe projection
The actual projection of the globe can be measured with an exophthalmometer.
The device rests on the orbital rims and measures the distance to the top of the cornea.
Usual values vary depending on the population but are often around 15 to 18 mm in adult men.
This value is less aesthetically interesting than the orbital vector, because the position of the globe must always be interpreted in relation to the bony structures surrounding it.
7. Eyebrows and top management
a. Eyebrow position
In men, the eyebrows are generally relatively close to the supraorbital rim.
A low eyebrow reduces the distance between the eye and the forehead and strengthens the framing of the eye region.
Conversely, a very high eyebrow leaves more visible space above the eye.
The exact measurement of this distance is less standardized than previous ratios. It is therefore more useful to observe the position of the eyebrow in relation to the supra-orbital rim and the upper eyelid.
b. Brow tilt
The inclination of the eyebrow is measured on a frontal photograph by comparing its general direction to the horizontal.
A slight positive inclination is generally sought in men, with approximately +5 to +13° as an order of magnitude.
The male eyebrow, however, generally remains straighter than a strongly arched eyebrow.
c. Brow ridge
The brow ridge or supra-orbital arch corresponds to the bony structure located above the eye.
A sufficiently projected brow ridge further frames the globe and accentuates its deep appearance.
It also helps to visually reduce upper eyelid exposure.
It must therefore be considered with the depth of the eye, the hooding and the position of the eyebrows rather than separately.
8. General shape sought
a. From the front
A sought-after shape generally has a relatively long and low opening.
The Eye Aspect Ratio is approximately between 2.9 and 3.5, with a central area near 3.1 to 3.3.
The canthal tilt is slightly positive, generally around +5 to +8.5°.
Each eye represents approximately 20% of the bizygomatic width.
The distance between the pupils is approximately 45 to 47% of the bizygomatic width.
The space between the medial canthi is approximately the length of an eye.
The upper eyelid remains minimally exposed and the lower eyelid comes close to the lower edge of the cornea, with little or no scleral show.
b. In profile
The eye is relatively contained in its orbit.
The brow ridge frames the upper part of the globe and the infra-orbital rim supports its lower part.
A positive orbital vector indicates that the structure under the eye has sufficient projection relative to the cornea.
The eye then appears less prominent and the transition between the lower eyelid and the cheekbone is more regular.
c. Set of characteristics
The often sought-after shape therefore combines eyes that are quite long horizontally, a slightly positive canthal tilt, little vertical exposure, spacing proportionate to the face and good orbital depth.
A single parameter is not enough. A canthal tilt of +7° does not necessarily give a good ocular region if the eyes are very round, strongly prominent or accompanied by a significant scleral show.
9. The main measures
a. Eye Aspect Ratio
Measurement: medial canthus length → lateral canthus ÷ vertical height between the two eyelids at the level of the pupil
Benchmark: 2.9 to 3.5
Central value: 3.1 to 3.3
b. Canthal tilt
Measurement: angle of the line medial canthus → lateral canthus relative to the horizontal
Marks: less than 0° = negative; 0° = neutral; +3 to +5° = slightly positive; +5 to +8.5° = marked but moderate positive; more than +10° = strongly positive
Central value: approximately +6 to +8°
c. Eye Separation Ratio
Measurement: distance left pupil → right pupil ÷ bizygomatic width
Benchmark: 0.45 to 0.47
Central value: approximately 0.46
d. Intercanthal spacing
Measurement: distance left medial canthus → right medial canthus ÷ length medial canthus → lateral canthus of one eye
Benchmark: 0.92 to 1.05
Central value: approximately 1
e. Length of eye relative to face
Measurement: medial canthus length → lateral canthus ÷ bizygomatic width × 100
Benchmark: 19.5 to 21.5%
Central value: approximately 20%
f. Total width of the eye region
Measurement: distance left lateral canthus → right lateral canthus ÷ bizygomatic width
Benchmark: 0.62 to 0.68
Central value: approximately 0.65
g. Upper Eyelid Exposure
Measurement: vertical distance upper edge of the eyelashes → visible crease of the eyelid at the level of the pupil
Mark: approximately 0 to 4 mm
Center value: approximately 2 to 4 mm for low exposure
h. Lower scleral show
Measurement: vertical distance lower edge of the cornea → edge of the lower eyelid
Mark: approximately 0 mm
i. MRD1
Measurement: distance central light reflection of the cornea → edge of the upper eyelid
Mark: approximately 3.5 to 5 mm
j. MRD2
Measurement: distance central light reflection of the cornea → edge of the lower eyelid
Mark: approximately 4 to 5.5 mm
k. Orbital vector
Measurement: angle between the corneal relationship → infra-orbital rim and the vertical on a strict profile
Marks: greater than 0° = positive; 0° = neutral; less than 0° = negative
Reference value: around +10°
l. Brow tilt
Measurement: angle between the general direction of the eyebrow from its medial part to its lateral part and the horizontal
Benchmark: approximately +5 to +13°
10. The most useful measures
To quickly describe the eyes, the most useful measurements are the Eye Aspect Ratio, the canthal tilt, the Eye Separation Ratio, the length of the eye in relation to the width of the face, the exposure of the upper eyelid, the scleral show and the orbital vector.
A set close to:
EAR: 3.1 to 3.3
Canthal tilt: +6 to +8°
ESR: approximately 0.46
PFL / bizygomatic width: approximately 20%
ICD / PFL: approximately 1
Scleral show: approximately 0 mm
Upper Eyelid Exposure: low
Orbital vector: positive
corresponds to relatively long eyes, compact vertically, slightly inclined upwards and well contained in their orbital frame.
