Free tool
Hair Growth Calculator: How Long Will My Hair Take to Grow?
Healthy hair grows about half an inch (1.25 cm) a month on average. Enter your length now and the length you want, and this free hair growth calculator for women shows how long it takes once trims are counted.
Reviewed by Hair Fairy Editorial · Updated
Measure from the scalp at the crown to the ends. Pull curls straight before you measure.
Enter your current and goal length and your timeline appears here.
How long it takes to grow 2 to 12 inches
At the average rate of half an inch a month. The right-hand column assumes a quarter-inch trim every 12 weeks.
| Length to grow | No trims | With trims |
|---|---|---|
| 2 in (5 cm) | 4 months | 5 months |
| 3 in (8 cm) | 6 months | 8 months |
| 4 in (10 cm) | 8 months | 10 months |
| 6 in (15 cm) | 1 year | 1 year and 3 months |
| 8 in (20 cm) | 1 year and 4 months | 1 year and 8 months |
| 10 in (25 cm) | 1 year and 8 months | 2 years and 1 month |
| 12 in (30 cm) | 2 years | 2 years and 6 months |
How to find your own growth rate
If you color your hair, measure your roots. Divide the regrowth by the number of weeks since your last color, then multiply by four for a monthly rate. If you don't color, pick one strand at the front, measure it, and measure it again four weeks later. Under 0.45 in (1.1 cm) a month, choose slower in the calculator; over 0.55 in (1.4 cm), choose faster.
What makes growing out take longer
- Breakage. Heat, bleach and rough brushing snap the ends, so you lose length as fast as it grows.
- Frequent or heavy trims. Ask for a dusting rather than a cut when all you need is healthy ends.
- Shaping cuts. Growing out a short cut usually means trimming the back and sides so the front can catch up.
The calculator is for healthy hair growing at a normal rate. If you're seeing sudden shedding or patches, or regrowing hair after medical treatment, ask a dermatologist or your care team what to expect.
Before you commit to months of growing, browse long and layered styles or read how often to get a haircut. Thinking of going the other way? The 2.25 rule calculator shows whether short hair is likely to suit you.
Common questions
How fast does hair grow?
Healthy scalp hair grows about half an inch (1.25 cm) per month on average, or roughly 6 inches (15 cm) a year. Your own growth rate can be a little faster or slower depending on genetics, age and health.
Does trimming my hair make it grow faster?
No. Growth happens at the scalp, and cutting the ends doesn't change it. Trims help you keep length by removing split ends before they break further up, but every trim also takes some length off, which is why the calculator counts them.
How long does it take to grow out a pixie into a bob?
Often somewhere between eight months and a year and a half. It depends on how short the pixie is, how long you want the bob, and how often you have the back and sides shaped so the grow-out looks intentional along the way.
Can I make my hair grow faster?
No product has been shown to speed up healthy hair growth. What you can change is how much length you keep: detangle gently, go easy on heat and bleach, and trim only as often as your ends need it.
Why does my hair seem stuck at the same length?
Usually the ends are breaking about as fast as new hair grows. Each hair also grows for up to about six years before it rests and sheds, which sets a natural maximum length that differs from person to person.
Does curly hair grow slower?
It often looks that way. Curls and coils shrink up as they dry, so months of growth can barely show in the mirror. Stretch a curl straight to measure it, and if your stretched length still changes slowly, choose the slower growth setting in the calculator.