Hairstyles for a Diamond Face
Written by the Know Your Face Shape team. Not yet reviewed by a licensed cosmetologist — we’re looking for one. If you are one and spot something wrong, tell us at hello@knowyourfaceshape.com and we’ll fix it and credit you. Published September 14, 2026. Last updated September 14, 2026.
On a diamond outline the cheekbones are the only wide point — the forehead sits inside them and the jaw inside them again — so the advice runs at both ends and never in the middle. Every cut below either fills the hairline, puts weight at the jaw, or does the two at once.
Side-swept or curtain fringe
adds width at the hairline, the narrowest row in the table, and it is the highest-value single change on this outline
Forehead ratio
Chin-length cut with the ends turned out
puts the fullest point of the silhouette below the narrow part instead of beside the wide part
Jaw ratio
Shoulder-length layers starting above the jaw
weight at the jaw with nothing added at cheekbone height — the two ends filled, the middle left alone
Jaw ratio
Waves carrying width at the jaw
the same move as the turned-out ends, with more material to work with
Jaw ratio
Textured crop with a swept fringe
the short version: it still fills the hairline, which is the half most short cuts skip
Forehead ratio
Long layers with a side part and weight left at the ends
long hair works here only when something is placed at both ends — the part at the top, the layers at the bottom
Forehead ratio
Organised by which end of the outline the cut adds to, because this is the only shape where the two ends need the same treatment and the middle needs the opposite.
Three Rows at an Extreme at Once
Typical range = our published prototype value ± one standard deviation, read at build time from the same constants the detector runs on.
| Feature | What it is | Typical for diamond |
|---|---|---|
| Forehead ratio | forehead width ÷ cheekbone width | 0.72 – 0.88 |
| Jaw ratio | jaw width ÷ cheekbone width | 0.60 – 0.84 |
| Chin taper | chin width ÷ jaw width | 0.22 – 0.38 |
The forehead ratio is the lowest in the table, matched only by triangle. The jaw ratio and the chin taper are the lowest too, matched only by heart. Between them the cheekbones stand alone as the widest point by a clear margin, which is the entire shape: one width, and both ends inside it.
The length ratio sits in the longer half of the table, so this outline is long as well as narrow at both ends rather than long and straight-sided the way an oblong is. That distinction matters for the advice below: an oblong needs shortening, a diamond needs filling, and the two are not the same job even though both rows are long.
One Width, Two Ends
Heart and diamond are the two shapes whose advice is most often merged, and the numbers say why that is a mistake. Both narrow to a point; both carry the lowest jaw ratio and the lowest chin taper in the table; both sit at the median on the jaw angle, so that feature separates neither of them from anything. What differs is the top. On heart the forehead is the widest point and the advice is to keep it quiet. On diamond the forehead is the narrowest, so the identical instruction leaves the outline narrower at the top than it already is.
So this page runs in two directions at once, and that is what makes it different from every other page here. Add at the hairline — a fringe, a sweep, texture above the temples. Add at the jaw — weight, waves, a line that lands low. Do not add at the cheekbones, which is the one place where volume can only make the shape more extreme.
Add at Both Ends, Never in the Middle
The forehead end
A side-swept or curtain fringe is the single highest-value change on this outline, because it adds width where the row has least of it. Texture and a little height above the temples do the same job from the side, and a part that is off-centre does it from a third direction.
What does not work is a slicked-back centre part, which exposes the full narrow hairline and makes the cheekbones look wider by contrast — the opposite of the intended effect. This is the one place on this page where the usual “keep the top flat” instruction for a wide forehead has to be reversed, and the reversal is the whole point of the shape.
The chin end
Chin-length and shoulder-length cuts carrying weight at the jaw, with layers starting above the jaw rather than at the cheekbone. Ends turned outward are worth asking for by name: they put the fullest point of the silhouette below the narrow part of the outline instead of beside the wide part.
Very long, straight, one-length hair is the version that skips this end entirely and leaves the taper from cheekbone to chin unopposed. Length is not the problem — the absence of anything placed at the bottom of it is.
The middle
Nothing goes here, and it is worth saying plainly because most volume-adding advice lands at cheekbone height by default. Layers cut at that line, wide curls sitting beside the cheekbones, heavy decoration or a strong parting at that height — all of it widens the point that is already widest and narrows both ends further by comparison.
If a cut you like puts its fullest point at cheekbone height, ask for it moved down to the jaw. That is a one-sentence change in the chair and it is the difference between this page's advice and its opposite.
Women's Cuts and Men's Cuts
Both are filling the same two ends and leaving the middle alone, but they do not have the same tools. On this outline a beard adds at the jaw directly, which is the position the women's list has to reach with layers, waves and turned-out ends.
Women's
A side-swept or curtain fringe at the top. At the bottom, a chin-length cut with the ends turned out, shoulder-length layers starting above the jaw, or waves carrying width at the jaw. Long hair belongs on this list only with a side part and weight left at the ends, so that something is placed at both extremes rather than at neither.
The check that catches most mistakes is where the fullest point of the silhouette sits. At cheekbone height it is working against the shape; at the hairline or at the jaw it is working with it. Asking for layers to start above the jaw moves the answer without changing the length, which is why it is the cheapest correction on this page.
Men's
A textured crop with the fringe swept to one side fills the hairline, which is the part most short cuts skip and the part this shape most needs. Length on top is worth keeping for the same reason, but flat rather than tall: height above the crown draws the eye up past the temples and leaves the narrow hairline on show.
Do not clip the sides to skin. Tight sides are the standard advice for a face whose width is the problem, and on this outline it is not — the cheekbones only read as wide because both ends sit inside them. Removing what little width there is at the sides strengthens that contrast instead of weakening it. Leave a little, and taper the line rather than blocking it out.
A beard is the lever with no equivalent in the women's list, and here it works in your favour: growth fuller along the jaw and trimmed close at the chin adds at the narrow end without adding at the point. The reverse — long at the chin, thin along the jaw — stretches the taper this page is trying to fill.
What to Avoid on a Diamond Face — and Which Measurement It Damages
Volume built at cheekbone height
widens the point already widest, and by contrast makes the narrow forehead and the narrow jaw look narrower still.
Forehead ratio
A slicked-back centre part
exposes the full narrow hairline, which is the feature this row has least of.
Forehead ratio
Very long, straight, one-length hair with no layers
leaves the taper from cheekbone to chin completely unopposed and adds nothing at the top end either.
Jaw ratio
A heavy blunt fringe cut straight across
covers the forehead but does not widen it, and adds a horizontal line at the narrowest part of the outline. Swept is the version that works.
Forehead ratio
If Your Numbers Sit Between Diamond and Heart
Diamond vs Heart
diamond 0.72 – 0.88 · heart 0.97 – 1.13
Diamond and heart are the tightest pair on this site, and the reason is arithmetic rather than stylistic: in the rule set the two rows carry the same jaw ratio, the same chin taper and the same jaw angle. Two features differ — the length ratio by less than the tolerance around it, and the forehead ratio by more. So one measurement, forehead width against cheekbone width, decides which of these two pages you should be reading, and the two give genuinely opposite instructions about the top of the head.
If your forehead ratio sits between the rows, do not average the advice — averaging is how a cut ends up adding at the cheekbones, which is wrong on both shapes. Take the half that is safe on either side: keep the volume off the cheekbones and put weight at or below the jaw. That overlap works whichever way the measurement lands, and it is why the two pages agree completely about the middle of the face even while disagreeing about the top.
What to Tell Your Stylist
The geometry on this page, translated into the sentences that survive a noisy salon.
- 1
“Add at the top and at the jaw, and keep it flat at my cheekbones” — the whole page in one sentence.
- 2
“Layers should start above my jaw, not at my cheekbones.”
- 3
“I want a fringe that sweeps to the side, not one cut straight across.”
- 4
“Turn the ends out rather than in.”
Check Your Own Numbers First
Every recommendation above assumes the label is right. If you have not confirmed it, the calculator takes four tape measurements and turns them into the same five ratios this page sorts cuts by — and it reports the margin against all seven shapes rather than forcing one. The detector does the same job from a photograph, and the quiz does it without any measuring at all.
Hairstyles for a Diamond Face: FAQ
What is the best hairstyle for a diamond face?
One that adds at both ends at once: a side-swept or curtain fringe, with a chin-length or shoulder-length cut carrying weight at the jaw. Either half on its own works; together they are what brings the outline closer to the proportions the rest of the table sits at, and no other shape on this site needs both ends filled the way this one does.
Can a diamond face pull off a fringe?
Better than most shapes, and for a specific reason: the forehead is the narrowest in the table, so a fringe adds where there is least. Swept to the side, or parted in the middle as a curtain. Not cut straight across, which covers the forehead without widening it and puts a horizontal line at the narrowest part of the outline.
Is a diamond face the same as a heart-shaped one?
No, and one measurement separates them. Both taper to a narrow chin and carry the same jaw, chin and jaw-angle values in the rule set. Heart is the only row where the forehead measures wider than the cheekbones; diamond is the row where the cheekbones stand alone as the widest point. The advice about the top of the head is opposite, so it is worth measuring before booking.
Should a diamond face avoid long hair?
Not the length — the absence of layers. Very long straight one-length hair puts nothing at either end and leaves the taper from cheekbone to chin unopposed. The same length with a swept fringe and layers starting above the jaw is on the recommended list, because both ends are filled and the middle is left alone.
Recommendations on this page come from this site’s own rule set — the five features, the prototype value each shape is centred on, and the tolerance around it, all published on /about and all of it the same code the detector runs. Nothing here is a percentage, a ranking we invented, or a claim about how often a shape occurs; we publish no accuracy figure on any page, because we could not verify one.