Korean Perm: Who It Suits, How Long It Lasts, Korean Perm vs Bio Perm

In short. A Korean perm gives the best result on healthy hair, including fine hair and hair that is coloured regularly. It is not for total blonde or powder-bleached hair, heavily damaged hair, years of keratin treatments or very short cuts, and it waits two weeks after fresh colour. A digital perm lasts 4-6 months, a cold perm 3-5. "Bio perm" is a Russian name for gentle perms without heat. The Korean cold perm is exactly that, so in Moscow it is rightly called a bio perm. The Korean digital perm uses heat on a machine and is a different procedure, not a bio perm.

Who gets the best result

The best Korean perm is done on healthy hair. That covers more people than you might think:

• coloured hair, even if you colour regularly and have for years, as long as it hasn't been bleached;
• fine hair, with the solution and heat chosen after a test strand, often as a cold perm;
• straight hair that won't hold a curl from a styler, which is one of the most common reasons people come;
• men's hair from 8 to 15 cm, where the perm gives a soft wave or a defined curl.

What you get is soft, shiny hair with a wave that moves, styles quickly and lasts for months. After washing the hair falls into a soft wave by itself; with a styler on top, defined curls hold for 3-5 days until the next wash.

Who should wait

These are the cases where I say "not now" or "not on this hair":

• Total blonde and powder bleaching. Bleaching removes most of the cuticle, and the cuticle is what holds a curl. The hair slips on the rod and the shape sags. Restoration comes first, then we decide by the test strand.
• Heavily damaged hair. Frequent bleaching, earlier perms, breakage along the length. Restoration first.
• Years of keratin or hair botox. Here the calendar doesn't help: after two years of keratin every three months the protein inside the hair has changed. A perm will give it shape but won't remove the frizz. A single keratin treatment is a different story.
• Very short cuts. A curl needs length to sit on. Hong Jihoon in Seoul doesn't perm very short hair at all, and I follow the same rule.
• Fresh colour. Not a no, just "not yet": two weeks between colour and perm.
• Pregnancy and breastfeeding, scalp conditions and active hair loss. The procedure is postponed.

There are also two expectations a Korean perm doesn't meet. It is a perm for styling, not ready-made curls 24/7 with no effort. And it gives a soft, natural wave, not tight small spirals.

How long a Korean perm lasts

A digital perm lasts 4-6 months, a cold perm 3-5. Where you land within that range depends on the hair and on care. Thick, healthy hair holds the shape longer; fine and porous hair, less. On long hair the ends relax first, because the weight of the length pulls the curl down.

I don't carry over the timings from Korean salon sites. In Seoul Hong Jihoon told me that Slavic hair is on average 20-30% finer than Korean hair, and called it a statistic rather than a rule. I see the difference in my own chair: on two of my Korean clients the same solution and machine gave a springy curl just like at the academy, while on Slavic hair the wave is softer.

The wave doesn't drop off suddenly. It softens step by step, the roots grow out straight, and the transition stays soft, with no hard line. My first perms at the studio were in April 2026, and six months later the clients came back for a repeat: the wave had relaxed calmly and the hair was healthy.

Korean perm vs bio perm

"Bio perm", biozavivka in Russian, is a name that appeared in Russia in the 2000s for ammonia-free perms on milder solutions, to set them apart from the classic perm. In Korea the name doesn't exist. There, a perm is digital, with heat on a machine, or cold, without one.

Strictly speaking every perm is chemical: the solution changes the shape, not the rod. What differs is the solution, its pH and whether heat is controlled.

In Moscow the Korean cold perm is what people mean by "Korean bio perm", and that name fits: no machine, no heat. The digital perm is sometimes sold under the same name, and that is a mistake. So the useful question is the content: is there a machine, which solution, and are the results shown on dry or wet hair. The cold method is covered in Korean Cold Perm, the machine in Digital Perm Machine, and the solutions in Korean Perm Solutions.

How the decision is made

Never by phone or by eye. Before booking I look at two photos in daylight and the colour history. Then, on every new head, I do a test strand in a hidden area at the lower back of the head and watch how the hair behaves with the solution. That is how it is done in Korea too: a test strand is part of every procedure. If the hair won't take it, I say so directly.