PlayInfoBox

Home /Beauty /Thermal Hair Straightening vs. Digital Perm: What's the Difference

Thermal Hair Straightening vs. Digital Perm: What's the Difference

Thermal straightening smooths curl away, while a digital perm builds wave in. Here's how the two processes and their results actually differ. Actual results and suitability vary by hair condition and salon, so treat this as general information.

How thermal straightening works

A softening solution is applied first to loosen the hair's internal bonds, then a flat iron at high heat presses the hair straight, and a second solution locks the new, straight shape in place. It's sometimes called Japanese straightening or rebonding.

How a digital perm works

After a softening solution is applied, hair is wound onto rods and processed with a heated digital styling machine to form the wave, then a second solution locks that shape in place.

How long results last, compared

Both treatments are commonly said to hold for roughly three to six months, though in both cases new growth eventually creates a visible line between the treated hair and your natural texture at the roots.

How much damage to expect, compared

Both rely on a combination of chemical processing and high heat, so both tend to put more stress on hair than a simple dye job.

Which hair type suits which treatment

If you want stubborn curl or texture smoothed into sleek, straight hair, thermal straightening is the usual choice; if you want natural-looking volume and wave, a digital perm is more often recommended.

Aftercare for either treatment

Keeping hair dry and avoiding tight ties or pressure on it for the first one to three days after either treatment helps the new shape set properly, and following up with protein treatments and a gentle shampoo afterward helps manage the stress placed on the hair.

Can you get both done on the same day?

Combining straightening and a perm in a single session puts a lot of chemical and heat stress on hair at once, so it's generally recommended to space the two treatments out rather than doing both back to back. Both thermal straightening and a digital perm apply heat on top of chemical processing, unlike a simple no-heat treatment β€” straightening presses curl flat with a hot iron, while a digital perm uses heat to build wave in with rods, which is the key difference between the two techniques even though both use heat toward opposite ends.

Does your natural hair type change how the results turn out?

Straight, wavy, and curly hair can all respond differently to the same treatment, producing different results and holding the style for different lengths of time. It helps to know your own hair type going in and discuss it with your stylist beforehand.

Frequently Asked Questions

Can I get either treatment while pregnant?

Because of the chemical fumes involved and the fatigue from a long salon session, it's commonly recommended to avoid or postpone either treatment during early or late pregnancy, and to check with a doctor first if you do want to go ahead.

Can I color my hair right after either treatment?

Both treatments put stress on hair, so it's recommended to wait a period β€” typically at least one to two weeks β€” to let hair recover before coloring, in order to limit additional damage.