Post-Acne Marks, Sun Spots or Melasma? How to Tell Which Dark Spot You Have

Post-acne marks sit exactly where a pimple, bite or scratch healed. Sun spots are small and show up only where the sun lands every day. Melasma appears as larger, matching patches on both sides of the face. The three look alike at a glance, and each one needs a slightly different routine.

By Mirabel, co-founder of IYASA. Mirabel started IYASA after years of looking for skincare that evens the look of skin tone without lightening it. She writes about what she has learned as a founder and a customer. This article is general skincare information, not medical advice.

One of the questions we get most: "Why is my dark spot not fading like everyone else's?" Often the answer is that it is a different kind of spot. On melanin-rich skin, three types show up again and again — and each asks for a slightly different approach.

A note on words: "dark spots" is an umbrella term. It covers all three types below.

1. Post-acne marks (post-inflammatory hyperpigmentation)

This is the most common type on melanin-rich skin. You will also see it called PIH, and it follows eczema, bug bites and scrapes as well as acne.

What they look like: flat brown or dark marks exactly where a pimple, bite, scratch or ingrown hair used to be. They often appear in clusters on the cheeks, jaw and chin.

Why they happen: inflammation tells skin to make extra pigment as it heals. The deeper or longer the inflammation, the darker and longer-lasting the mark.

What helps: stop the cycle first — hands off, no picking, calm the breakouts. Then a consistent brightening step such as vitamin C or niacinamide, daily sunscreen, and patience. Most marks fade noticeably over 8–12 weeks with a steady routine.

2. Sun spots

What they look like: small, evenly coloured spots on the areas that see the most sun — cheekbones, forehead, nose, hands and shoulders. They tend to darken in summer and soften a little in winter.

Why they happen: years of UV exposure. Melanin gives some natural protection, but not enough to stop pigment building up where sun lands every day.

What helps: sunscreen does most of the work here — SPF 30 or higher, broad spectrum, every morning, reapplied if you are outside. A brightening step helps even the look of the skin around the spots. See why SPF is a dark-spot product.

3. Melasma

What it looks like: larger, blotchy patches with soft edges, usually symmetrical — both cheeks, the upper lip, forehead or bridge of the nose.

Why it happens: a mix of hormones (pregnancy, birth control), sun and heat, and genetics. It is common in women with deeper skin tones.

What helps: melasma is stubborn and tends to come back, so it is worth seeing a doctor for a proper diagnosis and plan. Gentle, consistent care and strict sun and heat protection support that plan. Harsh products and bleaching creams can make it much worse — read what to avoid and why.

A quick way to tell them apart

• Was there a pimple or injury there first? Likely a post-acne mark.
• Small spots only where the sun hits? Likely sun spots.
• Large, matching patches on both sides of the face? Could be melasma — get it checked.

If you are unsure, or a spot is changing shape, growing, bleeding or itching, see a doctor. A dark spot that behaves unusually should always be looked at.

What all three have in common

• Daily sunscreen is non-negotiable.
• Gentle beats harsh — irritation darkens every kind of spot.
• Results take weeks, not days. Judge a routine after about 12 weeks.

For post-acne marks and everyday dark spots, the routine is in our step-by-step guide for melanin-rich skin, and the causes are in hyperpigmentation on dark skin.

Not sure where to start? Take the 60-second skin quiz — it matches your concern to a routine. And if you have a question about your own spots, leave it in the comments on our Sunday posts; we answer them every week.