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Lip Shape Detector: Find Your Lip Shape in Seconds

Upload a selfie or use your camera. Our AI maps 478 facial landmarks, measures your lips, and tells you which of the 9 lip shapes you have—with the numbers to back it up.

🔒 100% private · runs in your browser · nothing is uploaded
Quick answer: A lip shape detector is an AI tool that finds the outline of your lips in a photo and classifies them as full, thin, wide, round, heart-shaped, bow-shaped, top-heavy, bottom-heavy, or downturned. This one runs entirely on your device, shows a primary and secondary shape with confidence percentages, and gives you six real measurements—not just a label.

Try the Free Lip Shape Detector

Drop your photo here or tap to upload
JPG / PNG / WebP · front-facing · relaxed lips
Loading AI model…
✅ Relaxed, closed or slightly parted lips
✅ Camera level with your face, even light
❌ No big smile, pout, or duck face
❌ Skip heavy dark lipstick or overlining
Your primary lip shape

Results are a proportional estimate for styling guidance—not a medical assessment. Angle, expression, and lighting affect the numbers.

Key Facts About Lip Shape Detection

  • There are 9 commonly recognized lip shapes: full, thin, wide, round, heart-shaped, bow-shaped, top-heavy, bottom-heavy, and downturned.
  • This detector maps 478 facial landmarks and uses roughly 40 of them around the mouth to trace the outer and inner lip lines.
  • It reports 6 measurements: width-to-face ratio, fullness, upper-to-lower ratio, Cupid’s bow depth, corner tilt, and symmetry.
  • Most people are a combination of two shapes, so you get a primary shape plus a secondary trait with confidence percentages.
  • Processing is 100% on-device. No image is uploaded, transmitted, or stored.
  • Lip shape is genetic, but volume and definition change with age as collagen and fat decline.

How the Lip Shape Detector Works

The detector works in three steps: it locates your face, maps the lip contour with a landmark model, then converts the geometry into ratios that match named lip shapes.

  1. Face and landmark detection. A face-mesh model (Google MediaPipe Face Landmarker) places 478 points on your face directly in your browser. Around 40 of those points outline the vermilion border—the edge where the pink lip tissue meets skin.
  2. Roll correction and measurement. The tool levels the image using your eye line so a tilted head does not skew results, then measures mouth width against cheekbone width, upper and lower lip heights, the depth of the Cupid’s bow, the vertical position of the corners, and left-right balance.
  3. Classification. Each ratio is scored against thresholds derived from published anatomical averages. The highest score becomes your primary shape; the runner-up becomes your secondary trait. A “Natural (Balanced)” label appears when no single feature dominates.

Want to check the result by hand? Our printable lip shape chart walks you through the same three cues in a mirror.

The 9 Lip Shapes the Detector Can Identify

Every lip shape is just a description of how volume and outline are distributed. Here is what each label means and how the detector recognizes it.

Full lips

Plump upper and lower lips with even volume. Detected when fullness ratio is above ~0.42. Guide →

Thin lips

Low vertical height in both lips with a softer border. Detected when fullness falls below ~0.28. Guide →

Wide lips

Horizontal length dominates; the mouth spans more than ~42% of cheekbone-to-cheekbone width.

Round lips

Soft curves, a shallow Cupid’s bow, and compact width—the outline reads like an “O”.

Heart-shaped lips

Sharp, high Cupid’s bow with a fuller upper lip that tapers to the corners. Guide →

Bow-shaped lips

Defined double curve on the upper lip, but gentler peaks and more balanced volume than heart-shaped.

Top-heavy lips

The upper lip is visibly taller than the lower. Detected when the upper-to-lower ratio exceeds ~1.0.

Bottom-heavy lips

The lower lip carries most of the volume—the classic natural pout. Ratio below ~0.6.

Downturned lips

Corners sit lower than the center line at rest, which can read as serious regardless of mood.

See side-by-side illustrations of all nine in our types of lips guide.

Heart-Shaped vs. Bow-Shaped vs. Cupid’s Bow: What’s the Difference?

These three terms get mixed up constantly. The Cupid’s bow is a feature—the double curve at the center of the upper lip. Heart-shaped and bow-shaped are lip shapes defined by how pronounced that feature is and how it pairs with volume.

TermWhat it describesCupid’s bowUpper vs. lower lip
Cupid’s bowAn anatomical landmark, not a shapePresent on almost everyone
Heart-shaped lipsA lip shapeSharp, high peaks; deep dipUpper lip fuller, tapers to corners
Bow-shaped lipsA lip shapeDefined but softer peaksBalanced or slightly upper-leaning

What Your Measurements Mean

Unlike filters that only spit out a label, this detector shows the six numbers behind the result so you can see why you got it.

MetricHow it’s measuredTypical range
Width ratioMouth width ÷ cheekbone width0.34–0.42 (below = narrow, above = wide)
FullnessTotal lip height ÷ mouth width0.28–0.42 (below = thin, above = full)
Upper:lower ratioUpper lip height ÷ lower lip height at center0.6–0.9 is most common; many aesthetic guides cite ~1:1.6 as a classic proportion
Cupid’s bow depthPeak-to-dip height ÷ total lip heightAbove 0.10 = defined bow
Corner tiltCorner height vs. mouth center lineNeutral, up, or down
SymmetryLeft vs. right width and corner height90%+ is normal; perfect symmetry is rare

Curious how lip proportions fit into overall facial harmony? The Golden Ratio Face analyzer explains how the same landmark approach is used to score whole-face proportions.

Makeup Tips by Lip Shape

Once you know your shape, liner placement and finish do most of the work. Use this as a starting point, not a rulebook.

Lip shapeLiner strategyBest finishAvoid
FullLine on the natural edge; no overliningMatte or satinHeavy gloss (adds bulk)
ThinLine just outside the edge, mostly at centerGloss or sheer shimmerVery dark mattes
WideStop liner short of the cornersGloss at center onlyBright color to the corners
RoundExtend corners slightly to elongateMatte for structureCenter-only gloss
Heart-shapedDefine the bow precisely; soften peaks if desiredSatinOverlining the peaks
Bow-shapedTrace the arch cleanlySatin or creamBlurred edges
Top-heavySlightly overline the lower lip centerGloss on bottom onlyGloss on top lip
Bottom-heavySubtly overline the upper lip along the bowHighlight above the bowDark shade on top lip
DownturnedAngle liner upward at the outer edges; conceal below cornersSatinFollowing the corner downward

Does Lip Shape Change With Age? (And Does It Work for Men?)

Your lip shape is genetic and stays fairly consistent, but its volume and definition change with age. Collagen and fat decrease over time, the vermilion border softens, and lips can look thinner or less defined by your 40s than they did at 25. Sun exposure and hydration speed up or slow down that shift.

The detector works for everyone. Lip shape describes proportions—not gender, ethnicity, or age. The same six ratios are measured for every face.

Considering fillers or a lip flip? A neutral, measured baseline of your upper-to-lower ratio and Cupid’s bow depth is useful to bring to a consultation. Treat this tool as a conversation starter, not a treatment plan—your provider will assess anatomy in person.

How Accurate Is It? Our Honest Take

The landmark model is very consistent; the label is an interpretation. Anyone claiming a lip shape detector is “100% accurate” is overselling it. Here is what actually affects your result:

  • Expression: Smiling widens the mouth and flattens the Cupid’s bow. Pouting inflates fullness.
  • Camera angle: A phone held below your face exaggerates the lower lip; above it exaggerates the upper lip.
  • Makeup: Overlining and dark lipstick shift the detected border outward.
  • Lighting: Harsh side shadows can blur one corner and lower the symmetry score.

For the most reliable result, take two or three neutral photos and compare. If the primary shape is the same each time, trust it. If it flips between two labels, you are almost certainly a combination—which is normal and common.

Your Photo Never Leaves Your Device

The AI model downloads to your browser once (about 4 MB) and runs there. Your image is drawn onto a local canvas, analyzed, and discarded when you close the tab. There is no upload, no account, no server-side storage, and no facial data retained. Use the “Download Result Card” button only if you want to save or share it.

Lip Shape Detector FAQ

What is a lip shape detector?

A lip shape detector is an AI tool that analyzes a photo of your face, locates the outline of your lips using facial landmarks, and classifies them into a shape such as full, thin, heart-shaped, wide, round, top-heavy, bottom-heavy, bow-shaped, or downturned.

How do I know what lip shape I have without a tool?

Relax your mouth in front of a mirror and check three things: where the fullness sits (top, bottom, or even), how sharp your Cupid’s bow is, and whether your corners point down, straight, or up. Then compare against a lip shape chart.

Is my photo uploaded or stored?

No. All processing happens on your device inside your browser. Your photo never leaves your phone or computer and we do not store it.

What are the 9 lip shapes?

Full, thin, wide, round, heart-shaped, bow-shaped, top-heavy (heavy upper), bottom-heavy (heavy lower), and downturned. Many people are a combination of two.

Does it work for men?

Yes. Lip shape is a description of proportions, not gender. The detector measures the same ratios for every face.

Can I use it with lipstick on?

Yes, but nude or light shades give the cleanest border. Dark lipstick and overlining can push the detected edge outward and inflate your fullness score.

What is the difference between heart-shaped and bow-shaped lips?

Heart-shaped lips have a sharp, high Cupid’s bow and a fuller upper lip that tapers to the corners. Bow-shaped lips have a defined but softer double curve with more balanced upper and lower volume.

Can my lip shape change over time?

The underlying shape is genetic and stays consistent, but volume and definition decline with age as collagen and fat decrease, so lips can appear thinner or less defined.

Is this the same as the TikTok lip shape filter?

No. Filters overlay a pre-drawn chart on your face. This detector measures your actual lip landmarks and shows the numbers, which is why results are more consistent and explainable.

Not sure which shape you are?
Run the detector above, or take our 60-second lip shape quiz (no photo needed).

Sources & Methodology

  • Google MediaPipe Face Landmarker (478-point face mesh) — on-device landmark detection model.
  • Empire Medical Training, “Types of Lips & Lip Shapes: Complete Visual Guide” — lip anatomy and age-related change.
  • L’Oréal Paris USA, “How to Determine Your Lip Shape” — the 9-shape consumer taxonomy and combination shapes.
  • Charlotte Tilbury, “Different Types of Lip Shape” — identification cues and makeup techniques.
  • GoldenRatioFace.net — facial-proportion analysis context.

Editorial note: Rizwan Aslam personally tested this detector on a diverse set of faces (varying skin tones, ages, and genders) before publication. Thresholds are re-calibrated as new test data comes in.