How Fast Does Hair Grow? Hair Growth Rate by Age

Key Takeaways:

• Hair grows about half an inch per month on average — roughly 6 inches per year.

• Growth rate can vary by factors like genetics, hormones, diet, stress, and age.

• Hair growth rate by age can be slower for older adults due to shrinking follicles and hormone changes.
  

You shave your legs, and the stubble seems to pop up overnight. But when you want your hair to grow out after a too-short haircut, it feels like it takes forever.

If you’ve ever wondered how fast hair grows, we’ve got the answer.

Keep reading to learn how much hair grows each month (and year), how the hair growth cycle works, hair growth by age, and what might help speed things up.

It may seem like your hair grows slower (or faster, if you’re lucky) than those around you. But most people fall close to the average hair growth rate of about 0.35 millimeters (mm) a day, or roughly half an inch per month.

That means the typical person sees around 6 inches of new hair growth per year. Of course, factors like hormones, diet, and genetics can influence that rate. 

Your hair follicles go through three repeating stages: the anagen, catagen, and telogen phases — collectively known as the hair growth cycle.

Anagen Phase

The growth phase lasts anywhere from 2 to 6 years. And 85 to 95 percent of the hairs on your scalp are in this phase at any time.

Catagen Phase

This short transition phase lasts a few weeks. About 1 to 2 percent of your hair follicles are in the catagen phase at any given time.

During this stage, the hair follicle shrinks about one-sixth of its usual size. It detaches from its blood supply in preparation for shedding.

Telogen Phase

The resting phase lasts around three months. Typically, anywhere between 5 and 10 percent of your follicles are in the telogen phase. During this phase, the hair shaft remains in the scalp, but it doesn’t grow or change.

After the resting phase, old hairs fall out to make room for new ones. Most people shed 50 to 100 hairs a day — a completely normal amount. 

→ Learn more: How Much Hair Do You Lose in a Day?

A variety of factors can impact how quickly (or slowly) your hair grows.

Genetics

Your genes influence hair growth rate, thickness, and texture. Some people naturally have longer anagen phases, allowing their hair to grow longer before shedding.

Age

Hair tends to grow more slowly as you get older. The follicles shrink, the anagen phase shortens, and pigment production decreases, which contributes to thinning and graying hair.

As you age, you also become more prone to certain types of hair loss, like female or male pattern hair loss (androgenetic alopecia).

→ Read: How One Woman Found Confidence by Embracing Gray Hair

Hormones

Fluctuations in estrogen, testosterone, and thyroid hormones can affect hair growth. Drops in estrogen, such as during menopause, can lead to reduced hair density.

Diet and Nutrition

Protein, iron, zinc, and vitamins A, C, D, and E all play key roles in healthy hair growth. Certain nutrient deficiencies can make hair dull, brittle, or prone to shedding.

Stress

High stress levels can trigger telogen effluvium — a temporary condition that causes more hair follicles to enter the resting phase (and then subsequently shed). 

According to research, chronic stress may also keep follicles dormant for longer periods. These factors can affect how fast your hair grows.

Medical Conditions and Medications

Thyroid diseases (like hypothyroidism and hyperthyroidism), autoimmune disorders like alopecia areata, and certain medications can impact the hair cycle or slow growth.

Hair growth doesn’t stay the same throughout your life, but there’s no rigorous research to confirm hair growth rate by age. 

One study suggested that hair grows faster in childhood than in infancy, although this was only based on a study of 266 preschool-aged children.

You’re more likely to experience hair loss as you age. Women are more likely to experience androgenetic alopecia (female pattern hair loss) after menopause.

But this doesn’t necessarily mean the rate at which hair grows changes — rather, that aging may make you prone to certain hair loss conditions.  

With that said, it’s possible to experience hair loss at any age. If you think you’re experiencing hair loss, get treatment sooner rather than later — the earlier you treat it, the better. 

While there are no miracle treatments for overnight growth, some science-backed strategies can help promote healthier, fuller-looking hair.

Check Out Minoxidil

Minoxidil is a hair loss treatment that might speed up hair growth. It’s available as:

• Topical 2% minoxidil solution

• Topical 5% minoxidil foam

• A once-daily minoxidil pill

Though its mechanism of action isn’t totally understood, minoxidil seems to work by:

• Increasing blood flow in the scalp, which means your follicles get the nutrients they need to function properly

• Moving dormant follicles into the anagen (growth) phase

• Lengthening the growth period of your hair follicles

To curb hair loss, minoxidil is most effective when used consistently and early — ideally at the first sign of hair loss.

Platelet-Rich Plasma (PRP) Treatment

PRP therapy involves drawing a small amount of your blood, spinning it in a centrifuge to concentrate the platelets, and injecting that plasma into your scalp. The growth factors in platelets may help stimulate follicle activity and improve hair density.

A 2024 meta-analysis in the Journal of Cosmetic Dermatology found PRP to be effective for male androgenetic alopecia, showing increased hair thickness and count after three months of treatment. But the researchers noted that the current evidence isn’t super strong and more robust studies are needed.

Laser Hair Growth Treatment

Low-level laser therapy (LLLT) uses red or near-infrared light to stimulate follicles and increase cellular energy. It may help improve hair density in men and women with pattern hair loss.

Many devices, like laser combs or caps, are FDA-cleared for safety and can be used at home several times per week. While not a cure, LLLT can complement other treatments like minoxidil.

→ Learn more: Red Light Therapy for Hair Loss: Does It Work?

Healthy hair habits can help support regrowth. Though these tips won’t speed up the rate of hair growth, they can keep your hair healthy and reduce breakage.

Here’s what we recommend:

• Handle your hair gently. Avoid aggressive towel-drying when you step out of the shower, as this can cause breakage. Try not to brush or comb too hard.

• Know your hair type and cater to it. From straight hair to curly hair, there are several hair types. Knowing which type you have can ensure you choose products that are right for you.

• Care for your scalp. Scalp health is truly the root of healthy hair. Make sure to shampoo whenever your roots get oily, as excess buildup and sebum can lead to irritation and potentially hinder healthy growth.

• Cool it with heat styling. When using a hair dryer or a flat iron, use the lowest heat setting to prevent hair damage. And apply a heat protectant beforehand, if possible, to avoid split ends and brittle hair.

• Skip tight hairstyles. Tight ponytails, braids, and buns can cause hair breakage and traction alopecia over time. Instead, embrace looser styles.

• Give your hair a rest. To avoid chemical damage, schedule more time between hair color touch-ups, and don’t do multiple treatments at once. For example, if you relax and color your hair, space those things out.

• Eat whole foods. A healthy diet supports hair growth, as your hair needs nutrients like biotin and iron to grow properly. If you’re concerned that you have a vitamin deficiency, ask a healthcare provider about supplements.

Again, these tips might not grow hair faster — but if you’re dreaming of luscious, long hair, it’s important to practice good hair care habits. Good hair care will help your hair look and feel better, plus it’ll help you avoid brittle, damaged hair.

→ Read: What Does Damaged Hair Look Like?

Hair growth takes time. But there are things you can do to encourage healthy hair growth. And if you think you’re experiencing excessive hair shedding or thinning, a hair loss treatment might be the next step.

Here are the main takeaways about hair growth:

• Be patient. Hair grows about 0.35 millimeters per day — about half an inch per month or 6 inches a year.

• Many factors affect the speed of hair growth. This includes genetics, age, and hormones.

• Certain treatments can boost hair growth. Examples include minoxidil, laser hair growth treatment, or PRP therapy.  

• Healthy hair care habits can improve the look and feel of your hair. Take (gentle) care of your hair to reduce shedding, breakage, and hair damage.

If you have any concerns about hair growth, scalp health, or hair shedding, reach out to a healthcare professional. They can help identify the root cause of your issues and recommend a possible treatment plan.

See answers to frequently asked questions about how fast hair grows and hair growth rate by age.

How much does hair grow in a week?

Hair typically grows about an eighth of an inch per week — or roughly half an inch every month. But this is just an average. It varies by person.

How long does it take to grow hair 12 inches?

At an average rate of half an inch per month and 6 inches of growth per year, it takes about 2 years to grow 12 inches of hair.

What vitamins help hair grow faster?

Biotin, vitamin D, zinc, and iron are key for healthy hair growth. However, supplements only help if you have a nutrient deficiency.

Can stress stop hair from growing?

Yes. Stress can push hairs into the resting phase, leading to shedding that typically resolves within months. This is a type of hair loss called telogen effluvium.

Does cutting hair make it grow faster?

No, cutting hair doesn’t make it grow faster. Trimming the ends won’t affect the hair follicle or growth rate, but it helps prevent split ends, making hair appear healthier as it grows.

This article is for informational purposes only and does not constitute medical advice. The information contained herein is not a substitute for and should never be relied upon for professional medical advice. Always talk to your doctor about the risks and benefits of any treatment. Learn more about our editorial standards.