Types of nails, compared

Three questions sort them all

Length or no length: an overlay is a coat over your own nail that adds strength or color but no length. An extension adds length, built on a tip or on a paper or foil form.

Lamp or no lamp: gel never dries in air. It hardens only when it is cured under a UV or LED lamp, and every gel type below works that way.

Soak-off or file-off: a soak-off product softens in acetone and slides off. A file-off product doesn’t dissolve, so it has to be filed or drilled away.

Every type, side by side

Gel polish (soft gel)

• Length: none added
• Lamp: yes, for every coat
• Removal: an acetone soak
• Wear: two to three weeks, per Cleveland Clinic
• Done: in a salon or at home

CND Shellac

• Length: none added
• Lamp: yes, the CND lamp that is part of its system
• Removal: acetone, held on with remover wraps
• Wear: up to 21 days, in CND’s own words
• Done: in a salon, as CND sells it

Builder gel (BIAB, structured gel)

• Length: mostly none, though it can be built over tips
• Lamp: yes
• Removal: usually soaked off, and filled in between sets
• Wear: two to four weeks (Who What Wear), about three (Refinery29)
• Done: mostly in a salon

Hard gel

• Length: yes, or it is used as a strong overlay
• Lamp: yes
• Removal: filed off, since acetone can’t dissolve it
• Wear: two to four weeks, per Makeup.com
• Done: in a salon

Gel-X and other soft-gel tips

• Length: yes
• Lamp: yes
• Removal: soaked in acetone for roughly 15 to 20 minutes
• Wear: up to three to four weeks, Aprés claims
• Done: mostly in a salon, with some kits for home

Dip powder

• Length: none added
• Lamp: usually none, though some systems seal with UV
• Removal: 100% acetone
• Wear: up to four weeks, per the AAD and Cleveland Clinic
• Done: in a salon or at home

Acrylic

• Length: yes
• Lamp: none; the paste hardens in air
• Removal: filed, or soaked in acetone (the sources differ)
• Wear: filled every two to three weeks as the nail grows
• Done: mainly in a salon

Polygel (acrygel)

• Length: yes
• Lamp: yes
• Removal: the bulk is filed down
• Wear: none of the sources we opened gives a figure
• Done: in a salon or at home

Press-on nails

• Length: yes, until you take them off
• Lamp: none
• Removal: an acetone soak
• Wear: five to seven days in one tested review, up to two weeks in another guide
• Done: at home

Nail strips and gel strips

• Length: none added
• Lamp: only for semi-cured gel strips, for at least a minute
• Removal: gel strips lift off with a wooden stick soaked in acetone
• Wear: roughly two weeks for gel strips
• Done: at home

Nail polish

• Length: none added
• Lamp: none; it air-dries
• Removal: ordinary polish remover
• Wear: the medical pages we read give no figure
• Done: anywhere

Where the sources disagree

• Acrylic: the American Academy of Dermatology (AAD) says soak it in acetone or file it; Who What Wear says it has to be filed.
• Builder gel: one expert says BIAB soaks off, while Refinery29 treats structured gel as a hard gel for a pro to remove. It depends on the product.
• Soft gel fills: Makeup.com says soft gel can’t be filled; Who What Wear says BIAB, a soft builder gel, can.
• Press-ons: Who What Wear says up to two weeks, and Grazia’s testers found closer to five to seven days.
• Long-wear polish: about a week, says Who What Wear; 15 to 16 days, say Essie and Sally Hansen of their own, with a fresh top coat on day 7.

The lamp question

Seven of these eleven are cured under a UV or LED lamp, and doctors and the industry don’t agree on how much that matters. The AAD says repeated gel manicures can raise the risk of skin cancer, and suggests asking for LED, which gives off less UV. Cleveland Clinic says the risk is low but still there, and that LED lamps emit UV too. A 2023 lab study found DNA damage in cells but no direct evidence in people. RadTech, a UV-industry group, calls the lamps safe when used properly.

Older comparisons on Polishpedia

Polishpedia put a Shellac manicure up against acrylic nails years ago, and that page is still here.

Shellac Manicure vs Acrylic Nails

Try one on first

Put a shape, a polish and nail art on a drawn hand in your skin tone, then find a nail salon near you and ask which of these it offers.

✦ Try a look on a hand

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