The Quick Answer

A keratin treatment and a Brazilian Blowout both smooth your hair, reduce frizz, and add shine, but they do it differently and deliver different results.

Choose a keratin treatment if you want maximum smoothing and straightening, longer-lasting results (3–5 months), and don’t mind waiting 48–72 hours before washing your hair.

Choose a Brazilian Blowout if you want to keep your natural curls or waves while eliminating frizz, prefer a faster appointment, and want to wash and style your hair the same day.

At Numi Hair Salon in Scarsdale, our stylists are trained in both treatments plus several other smoothing options, so we can recommend the best fit based on your hair type, lifestyle, and goals.

What Is a Keratin Treatment?

A keratin treatment is a professional smoothing service that infuses your hair with keratin, a natural protein that makes up about 90% of your hair’s structure. Over time, heat, chemicals, and environmental exposure strip keratin from your hair, leaving it frizzy, dry, and hard to manage. A keratin treatment restores what’s been lost.

How it works: Your stylist washes your hair with a clarifying shampoo, applies a keratin-infused formula section by section, blow-dries, and seals the treatment with a flat iron. The keratin bonds to your hair shaft, smoothing the cuticle from the inside out.

The results: Significantly smoother, straighter hair with dramatically less frizz. Hair feels stronger, shinier, and easier to style. The effect is more intense than a Brazilian Blowout; if you want your hair noticeably straighter, this is the treatment to choose.

The catch: You need to wait 48–72 hours before washing your hair or getting it wet. During that time, you can’t tie it up, tuck it behind your ears, or use clips, anything that creates a crease. The treatment time is also longer (2–3.5 hours).

At Numi Hair, we offer several keratin treatment options:

What Is a Brazilian Blowout?

A Brazilian Blowout is a specific type of smoothing treatment that uses a liquid keratin formula to coat the outside of each hair strand, creating a protective layer that seals the cuticle and blocks humidity.

How it works: Similar process — clarifying wash, section-by-section application, blow-dry, and flat iron. But the formula and technique are different. A Brazilian Blowout coats the hair rather than penetrating the shaft, which is why the results are less intense but more flexible.

The results: Smoother, shinier hair with frizz under control, but you keep your natural texture. Curls and waves stay; they’re just more defined and manageable. It’s a “your hair but better” result rather than a dramatic straightening.

The advantage: Zero downtime. You can wash, tie up, and style your hair immediately after the treatment. The appointment is also faster (1.5–2.5 hours vs. 2–3.5 hours for a traditional keratin).

Keratin vs. Brazilian Blowout: Side-by-Side Comparison

Keratin Treatment Brazilian Blowout
How It Works Penetrates the hair shaft, rebuilds keratin from inside Coats the hair strand, seals cuticle from outside
Smoothing Level Intense — significantly straighter Moderate — reduces frizz, keeps natural texture
Lasts 3–5 months 3–4 months
Treatment Time 2–3.5 hours 1.5–2.5 hours
Wait to Wash 48–72 hours Same day
Cost at Numi $350+ $350+
Best For Maximum straightening, thick/coarse hair, long-lasting results Frizz control while keeping curls/waves, convenience
Natural Texture Significantly relaxed — curls loosen noticeably Preserved — curls/waves stay, just smoother

The bottom line: if you want straighter hair, go keratin. If you want your natural texture minus the frizz, go Brazilian Blowout.

Which One Lasts Longer?

Keratin treatments last longer — typically 3 to 5 months vs. 3 to 4 months for a Brazilian Blowout. Some keratin clients stretch it to 6 months, depending on their hair type and maintenance.

Both treatments fade gradually with no harsh grow-out line. Your hair slowly returns to its natural state, which means you won’t have an obvious “before and after” moment  just a gradual transition.

To maximize the lifespan of either treatment:

  • Use sulfate-free shampoo and conditioner. We recommend Kerastase, Olaplex, or Oribe
  • Wash every 2–3 days, not daily
  • Minimize heat styling (you won’t need as much anyway)
  • Avoid chlorine and salt water

For more details on Brazilian Blowout timing specifically, read our guide on how long a Brazilian Blowout lasts.

Which One Is Better for Curly Hair?

This depends on what you want your curls to do after the treatment.

Want to keep your curls but eliminate frizz? Go with a Brazilian Blowout. It smooths the cuticle without altering your curl pattern. You’ll still have curls, they’ll just be more defined, less frizzy, and easier to style.

Want to relax your curls significantly? A keratin treatment will loosen your curl pattern noticeably. You’ll go from tight curls to loose waves, or from wavy to nearly straight. The effect is more dramatic.

Want something in between? The Magic Sleek Treatment is a great middle ground; it smooths without the harsh chemicals found in some traditional keratin formulas, and it works particularly well on textured and curly hair.

For a comprehensive guide, read our post on keratin treatment for curly hair.

Which One Is Safer?

Both treatments are safe when performed by a qualified stylist using professional products. The safety conversation usually centers on two things: formaldehyde and heat damage.

Formaldehyde: Some keratin treatment formulas (including some Brazilian Blowout formulas) contain formaldehyde or formaldehyde-releasing chemicals. Modern professional formulas have significantly reduced these levels, and many are now completely formaldehyde-free. At Numi, we offer a formaldehyde-free Keratin Complex option for clients who want zero chemical exposure.

Heat damage: Both treatments use a flat iron at high temperatures (380–450°F) to seal the formula. In the hands of an inexperienced stylist, this can damage hair. At Numi, our stylists are trained to adjust temperature and technique based on your specific hair type to minimize risk.

The safest approach: Space treatments at least 3–4 months apart, use professional aftercare products, and add bond-building treatments like Olaplex or K18 between appointments to keep your hair strong and healthy.

For a deeper dive into the risks, read our guide on whether a Brazilian Blowout can damage your hair.

Which One Costs More?

At Numi Hair, both treatments start at $350+. The final price depends on your hair’s length, thickness, and condition. Your stylist will give you a personalized quote during your consultation.

While the upfront cost is similar, here’s how they compare long-term:

  • Keratin treatment: $350+ every 3–5 months = roughly 2–3 treatments per year
  • Brazilian Blowout: $350+ every 3–4 months = roughly 3–4 treatments per year

So a keratin treatment is slightly more cost-effective over a full year because it lasts longer. But the Brazilian Blowout is faster per appointment and has no downtime, which has its own value.

For a full cost breakdown, read our guide on how much a Brazilian Blowout costs.

Book a consultation at Numi Hair to get an exact quote for your hair.

How to Decide Which Treatment Is Right for You

Still not sure? Here’s a quick decision guide:

Go with a Keratin Treatment if you:

  • Want your hair significantly straighter
  • Have thick, coarse, or very curly hair
  • Don’t mind the 48–72 hour wash waiting period
  • Want the longest-lasting results possible
  • Are okay with your curl pattern loosening

Go with a Brazilian Blowout if you:

  • Want to keep your natural curls or waves
  • Just want to eliminate frizz and add shine
  • Need to wash or style your hair the same day
  • Prefer a shorter appointment time
  • Want a more subtle, “your hair but better” result

Not sure? That’s exactly what consultations are for. Your Numi stylist will look at your hair’s type, condition, and texture, ask about your styling goals and daily routine, and recommend the treatment that makes the most sense. Sometimes the answer is neither; it might be a Magic Sleek or a Keratin Express instead.

Other Smoothing Options at Numi Hair

Keratin and Brazilian Blowout aren’t your only choices. Here’s the full menu of smoothing treatments at Numi:

Lasio Keratin — $350+. An intense smoothing treatment that works especially well on thick, coarse, and very curly hair. Longer-lasting than a Brazilian Blowout with more dramatic straightening.

Keratin Complex (Formaldehyde-Free) — $350+. All the benefits of a traditional keratin treatment with zero formaldehyde. Great for clients who want maximum safety.

Magic Sleek — $375+. Uses fewer harsh chemicals with a focus on deep nourishment. Excellent for color-treated, sensitive, or damaged hair.

Olaplex — $25+. A bond-building treatment that repairs damage at the molecular level. Not a smoothing treatment, but the perfect add-on to any keratin or Brazilian Blowout to protect your hair during processing.

K18 Treatment — $20. Another bond-repair option that reverses damage from heat, chemicals, and mechanical stress. Great as a standalone or add-on.

Kerastase Power Dose — $25+. A concentrated booster treatment customized to your hair’s specific needs: hydration, strength, shine, or volume.

Why Choose Numi Hair

993+ Google Reviews at 4.9 Stars. Our clients consistently rate us as the best salon in Westchester, and our smoothing treatment results speak for themselves.

Named a Top 100 Salon in the U.S. Numi Hair has been recognized nationally for quality, service, and results.

Multiple Best of Westchester Awards. Year after year, our team earns top honors from Westchester Magazine.

Trained in Every Smoothing System. Our stylists don’t just do one treatment; they’re trained in Brazilian Blowout, Lasio, Keratin Complex, and Magic Sleek. That means they recommend what’s best for your hair, not just what’s easiest.

Premium Products. We use and recommend Olaplex, Kerastase, and Oribe to protect your hair and maintain your results.

Ready to Book?

Not sure which smoothing treatment is right for you? Book a consultation and let your stylist assess your hair and walk you through the options. There’s no pressure, just honest advice.

Book your consultation at Numi Hair →

Or call us at 914-574-6402 to schedule.

FAQ

What’s the main difference between a keratin treatment and a Brazilian Blowout?

A keratin treatment penetrates the hair shaft for intense smoothing and straightening that lasts 3–5 months. A Brazilian Blowout coats the outside of the strand for frizz reduction while preserving your natural texture, lasting 3–4 months. Keratin gives you straighter hair; a Brazilian Blowout gives you your natural hair minus the frizz.

Can I get a keratin treatment on color-treated hair?

Yes, both treatments are safe for color-treated hair. In fact, they can help seal in your color and add extra shine. Just let your stylist know about any recent coloring so they can adjust the approach.

Which treatment is better for fine hair?

A Brazilian Blowout is generally better for fine hair because it’s lighter and less likely to weigh your hair down. Traditional keratin treatments can sometimes make fine hair feel flat. Your stylist may also recommend the Keratin Express Treatment as a gentler option.

How do I maintain my results?

For both treatments: use sulfate-free shampoo and conditioner from brands like Olaplex, Kerastase, or Oribe. Wash every 2–3 days, minimize heat styling, and avoid chlorine and salt water.

Can I switch between keratin and Brazilian Blowout?

Absolutely. Many clients alternate based on the season or their current hair goals. You might get a Brazilian Blowout in spring for a lighter touch, then a full keratin treatment before winter for more intense smoothing. Your stylist can help you plan.

How much do these treatments cost at Numi Hair?

Both start at $350+ at Numi Hair. The exact price depends on your hair’s length, thickness, and condition. Book a consultation for a personalized quote. For a full cost breakdown, read our Brazilian Blowout pricing guide.

Numi Hair Salon is located at 69 Harney Road, Scarsdale, NY 10583. We serve clients from across Westchester County, including Scarsdale, White Plains, Eastchester, Bronxville, Yonkers, and Hartsdale. Book your appointment today →