Face Zones in Skin Analysis: T-Zone, U-Zone and Per-Area Scores

Face zones in skin analysis are the areas a scan reads separately: the T-zone (forehead, nose and chin), the U-zone (cheeks and jawline), the under-eyes and the skin around the mouth. Scores differ by zone because the skin itself differs. Studies show the T-zone produces more oil than the cheeks, while redness, pigment and water loss each concentrate in different places on the face.

Below: what the T-zone and U-zone are, what research says about how they differ, how to read a per-area breakdown without overreacting, and how to use it to adjust which products go where.

What are the T-zone and U-zone?

The T-zone is the T-shaped strip across your forehead and down your nose to your chin; the U-zone is the curve of your cheeks and jawline around it. The American Academy of Dermatology (AAD) describes the T-zone as the forehead, nose and chin, and the split goes back to sebum research: a Korean study that measured oil at five sites on the face for a year found that the forehead, nose and chin produced more sebum than both cheeks, and proposed defining combination skin by comparing the T- and U-zones.

Apps that report by area usually go a step further and add smaller regions, because two of the most noticeable concerns live outside the classic T and U: lines and darkness under the eyes, and texture or breakouts around the mouth. How an app finds these regions on your face is covered in face mesh landmarks explained.

Why do skin scores differ by zone?

Scores differ by zone because oil, blood flow, water loss and pigment are measurably different from one part of the face to another, even on healthy skin. Three studies that measured these properties with instruments give a consistent picture.

Skin conditions follow zones too. The AAD says rosacea usually develops across the nose and cheeks, with redness in the center of the face. Melasma patches usually appear on the cheeks, forehead, chin and above the upper lip.

Then there is the camera. The nose sticks out toward the lens, the sides of the face curve away from it, and light falls differently on each. A per-area score blends real skin differences with these photographic ones, which is why the same zone compared over time tells you more than two zones compared with each other.

How do you read a per-area skin breakdown?

Read a per-area breakdown by looking for the zone that drags the overall score down and then watching that zone over several scans. A step-by-step approach:

1. Find the spread. An overall score of 70 can mean every area sits near 70, or that one zone is far below the rest. The second case tells you where to focus. Our guide to what a skin score means covers the overall number.
2. Expect some zones to score lower on certain measures. Visible pores and shine on the nose and forehead are normal for many people, given how much more oil the T-zone produces. A low pore score on the nose with good cheeks is a common, healthy pattern.
3. Compare each zone with itself. Track the cheek against last month's cheek. Comparing your forehead score with your cheek score mixes skin differences with differences in angle and light.
4. Check left against right. A drop on one side only deserves a second look. It can come from light hitting one side, a slightly turned head, or a real one-sided cause such as the side you sleep on or hold your phone against.
5. Wait for a trend. One low reading is noise. The same zone moving in the same direction over three or more scans taken the same way is a signal.

How should you adjust products by face zone?

Adjust products by zone by keeping the basics on your whole face and moving only the lighter, richer or active steps to the areas that need them. AAD dermatologists tell people with combination skin to treat their face as though it's two faces: moisturize the dry spots and skip the oily areas. In practice:

• Moisturizer by texture. A gel or light lotion on the T-zone, a cream on dry cheeks, or one moisturizer applied more heavily where you're dry.
• Oil-control actives where the oil is. The AAD notes that salicylic, glycolic and lactic acid can help reduce oiliness but may be too harsh, and says to stop or use them less often if your skin becomes irritated. Putting them on the nose and forehead only keeps them off drier cheeks. Our guide to salicylic acid for blackheads explains how BHA works in pores.
• Acne treatment on the whole acne-prone area. Zone thinking shouldn't shrink acne treatment down to single spots. The AAD advises spreading a thin layer of acne medication over all acne-prone skin to treat existing acne and prevent new breakouts.
• Sunscreen everywhere. Zone-by-zone care never applies to sun protection. The AAD recommends broad-spectrum SPF 30 or higher even for oily skin, and daily sunscreen is part of protecting every zone from sun damage, wrinkles and age spots.

Change one zone's product at a time and give it several weeks before you judge, or you won't know which change moved which score. For a full plan, see our combination skin routine.

Do face zone scores change with the seasons?

Yes, and the gap between zones can change too. In the Korean sebum study, summer was the highest sebum-secreting season, with seasonal variations in both the T- and U-zones. The authors found that a mismatch between the two zones in more than two seasons came closest to what people describe as combination skin. So a T-zone that shines in July and cheeks that feel tight in January are both expected, and a zone breakdown is most useful when you compare it with the same season last year or with the scans just before and after a product change. If your cheeks and T-zone seem to be moving in opposite directions, oily T-zone, dry cheeks explains why.

When does a zone pattern need a dermatologist?

See a dermatologist when a zone pattern points to a condition rather than a skin type: persistent redness or flushing in the center of the face, acne-like bumps on the cheeks that won't clear, or visible blood vessels, which the AAD lists among the signs of rosacea; or brown or gray-brown patches on the cheeks, forehead or upper lip, which can be melasma. Acne that hasn't cleared with treatment you can buy without a prescription is also worth a visit, according to the AAD. Any mole or spot that is new, changing or bleeding needs an in-person check, whatever a scan says.

How does a selfie scan help you track your skin by area?

A selfie scan helps because it reads the same regions the same way every time, which is hard to do by eye in a bathroom mirror. Pori, our iPhone app, maps a 468-point face mesh and has an AI vision model read your face region by region, then returns an overall skin score from 0 to 100 with scores for Hydration & Moisture, Pores & Texture, Pigmentation & Tone, Anti-aging & Elasticity and Overall health. Before/after comparison and progress charts let you see whether a zone-by-zone change is paying off, and the ingredient scanner (Pro) flags each ingredient in a product as beneficial, use with caution or avoid for your skin type before you put it on your T-zone or cheeks. The first scan is free; Pro is $9.99 a week with a 3-day trial for eligible Apple IDs or $49.99 a year (US, as of October 2026).

A scan describes how your skin looks in a photo. It isn't a diagnosis, and it doesn't check moles.