A shade coordinate you can take to any counter

What a photograph can and cannot settle

The shade-matching apps that name a specific product are answering a question the input does not contain. Four separate things stand in the way.

Shade names are not comparable between brands — a 3 in one range sits where a 20 sits in another. Formulas are reworked between batches, so the same name shifts over time. Products oxidise differently depending on skin chemistry, which changes the match an hour after application. And the differences between adjacent shades in a range are smaller than the error a photograph introduces through lighting alone.

What survives all four is a coordinate: your depth on a standard scale and your undertone column. That is portable, it does not go stale, and it narrows a wall of forty bottles to three worth swatching.

Depth, measured as ITA

Individual Typology Angle is the standard measure of skin depth in dermatology. It combines lightness and yellowness into one angle rather than using lightness alone, because melanin adds yellowness as well as darkness — so ITA tracks perceived depth considerably better than an L value does.

Above 55 degrees is very light, 41 to 55 light, 28 to 41 intermediate, 10 to 28 tan, minus 30 to 10 brown, and below minus 30 dark. The tool maps that onto a ten-point retail scale so you can compare a Fair-to-Light in one range against a 2.5 in another.

Why the jaw and not the hand

The back of the hand is a different depth from the face for most people, often by a full shade, because it collects far more sun over a lifetime. Swatching there is the most common matching error there is.

The jaw is the right place because it lets you judge the swatch against the face and the neck at the same time, which is what prevents a visible line. This tool samples along the jaw for the same reason, and separately samples the cheeks so it can tell you how far apart they are. When the two differ by more than about three points of lightness, matching to something between them usually beats matching to either.

How ranges are labelled

Testing a shade properly

Once the coordinate has narrowed things down, the test is behavioural rather than visual, and it takes an hour rather than a moment.

The oxidation test beats every tool, including this one

If you take one thing from this page, take this. Most foundations darken and warm over the first hour as they react with skin oils and air. A shade that matched perfectly when you put it on and reads orange at lunchtime was too warm to begin with; one that looks grey or chalky in daylight was too cool.

That drift is measuring the interaction between one specific formula and your specific skin, which is the actual question, and no photograph can anticipate it. A measurement tool narrows the field. Wearing the thing for an hour decides it.

Things that move the reading

Measure bare-faced. Foundation, tinted moisturiser and SPF with a cast all shift the result, sometimes further than the gap between adjacent depth levels. A recent tan moves you warmer and deeper than your baseline, which is real — it is the shade you need now rather than the shade you need in February, and most people genuinely do want two.

Flushing, rosacea, recent exercise and alcohol all push the reading cooler and redder for a while. If your face is flushed, wait.

This tool analyses a photograph on your device and transmits nothing. It produces a shopping coordinate, not a shade recommendation, and does not endorse or partner with any brand. Cosmetic products vary in how they behave on skin; always test before buying where you can.

Questions people ask

Why won't it just tell me my shade in a specific brand?

Because it cannot know it, and neither can any other photo tool. Shade names are not comparable between brands, formulas are reworked between batches, the same shade oxidises differently on different skin, and a photograph cannot resolve the quarter-step differences that separate adjacent shades. A tool that answers with a specific shade name is guessing in a confident voice. What a photo can give you is a coordinate — how deep your skin is and which undertone column to shop in — which works at every counter instead of one.

What is ITA?

Individual Typology Angle, the standard measure of skin depth in dermatology. It combines lightness and yellowness into a single angle rather than using lightness alone, which tracks perceived depth much better because melanin adds yellowness as well as darkness. Above 55 degrees is very light, below minus 30 is dark, and the bands between are used consistently across research.

Why sample along the jaw rather than the cheek?

Because that is where foundation is matched. The jaw lets you judge a swatch against the face and the neck at once, which is what stops a visible line at the jawline. The tool samples both and reports the difference, because when cheeks and jaw differ by more than a few points of lightness you usually do better matching between them than to either.

Is it true that MAC's NC shades are for warm skin?

Yes, and it is the most misunderstood labelling in the industry. NC stands for Neutral Cool and is formulated for warm, golden and olive skin; NW stands for Neutral Warm and is for cool, pink and red-toned skin. The letters describe the pigment balance the product adds rather than the skin it suits, which is exactly backwards from how everyone reads them.

Why does my foundation turn orange during the day?

Oxidation. Most foundations darken and warm over the first hour as they react with skin oils and air. If a shade matches on application and reads orange by lunchtime, it was too warm to start with. That drift is genuinely the most reliable undertone test available — better than anything you can judge at the moment of application, and better than this tool.

Should I match my face or my neck?

Often somewhere between the two. Faces and necks are frequently different depths, because faces get more sun and more product over the years. Matching the face exactly can leave a visible line at the jaw. Swatch along the jawline, look at it in daylight, and choose the shade that makes the boundary hardest to find.