The best retinol serums and retinoids, ranked by evidence.

On our scores, PURITO Retinol Retinal 2000 NAD+ Serum (4.5 efficacy) leads the retinol serums, with Theramid Clinical Vitamin A and celimax The Vita-A Retinol Shot close behind. The Ordinary Retinol 1% in Squalane scored 4.2 and is the best value. See the full rankings.

Retinal is one conversion step closer to the active form, so it works faster and more strongly at a lower percentage, and it's usually a little more irritating. In our database retinal products average 4.25 for efficacy against 4.02 for retinol. Retinol is the gentler place to start.

Retin-A is a brand of tretinoin, the active form of vitamin A, and needs a prescription. Retinol is a cosmetic ingredient your skin has to convert twice before it works, so it's slower and gentler.

For acne, adapalene: it's an acne drug with guideline support, sold at 0.1% without a prescription. For fine lines and texture, retinol or retinal, which are tested on aging skin. Don't layer them; pick one.

For acne, usually around 12 weeks for clear results. For fine lines and sun damage, several months; the classic tretinoin trial measured changes at 16 weeks, and improvement continues with longer use.

Usually a few weeks. Breakouts in the first weeks of a retinoid are common; if they continue past about six weeks, or your skin is raw or burning, ask your prescriber.

Creams are more moisturizing and usually suit dry or sensitive skin; gels are lighter and often suit oily skin, but many contain alcohol and can be more drying. Your prescriber chooses the strength and base.

Creams at 0.025%, 0.05% and 0.1%; gels at 0.01% and 0.025%; microsphere gels from 0.04% to 0.1%; and a 0.05% lotion. Higher isn't automatically better: many people start at the lowest strength.

No. Retinoids, including tretinoin, retinol and adapalene, should be avoided when pregnant, trying to conceive or breastfeeding unless your doctor says otherwise. Ask about azelaic acid instead.

Yes, but not at the same time at first. Use them on alternate nights, or salicylic acid in the morning, so your skin doesn't get over-dried.

Yes. Niacinamide is well tolerated and can make a retinoid easier to live with. Apply it after the tretinoin, or in the morning.

Yes, it's a common combination for acne and dark marks. Many people use azelaic acid in the morning and tretinoin at night. See our azelaic acid guide.

A gentle, fragrance-free cleanser and a plain moisturizer with ceramides or glycerin. See the cleansers and moisturizers in our sensitive skin rankings.

Any broad-spectrum SPF 30 or higher you'll wear every day, ideally fragrance-free. Retinoids make skin more sensitive to sun, so daily sunscreen isn't optional.

It can be, at a low strength. Start with a 0.2–0.3% retinol or a retinal serum two nights a week, over a moisturizer, and build up slowly. If it still stings, ask a dermatologist; azelaic acid or bakuchiol are gentler options.

Yes. Use it before the expiry date on the tube, keep it closed and away from heat and light, and ask your pharmacist if it changes colour or texture.