Hair Growth Calculator
Enter your current length, your goal length, and your growth rate to see roughly how long it'll take — plus a month-by-month checkpoint chart.
Growth checkpoints
Growth rates vary by genetics, health, and hair care — this is an estimate, not a guarantee.
What is the Hair Growth Calculator?
The Hair Growth Calculator is a free tool that estimates how many months it will take to reach your goal hair length. Enter your current length, your goal length and your monthly growth rate, and you’ll get a target date with month-by-month checkpoints. It’s handy for planning a grow-out or tracking your progress.
How it works
- Enter your current hair length.
- Enter your goal length.
- Enter your monthly growth rate (the average is about 0.5 inch, or 1.25 cm).
- Get the number of months, a target date and checkpoints along the way.
Why your result may differ from real life
The calculator shows how much your hair grows, not how much length you keep. If your ends break or split as fast as new hair comes in, you won’t see the full gain. Curly and coily hair can also look shorter than its real length because of shrinkage. Reducing heat, detangling gently and trimming split ends helps you hold on to more of what you grow.
Tips for using it
- Measure from the same spot each time, for example from the roots to the ends of your longest layer.
- Measure your hair when it’s stretched or straight, especially if it’s curly or coily.
- Check back every few months, since hair changes slowly and week-to-week differences are too small to notice.
What to do next
- Read our Hair Growth Guide to see what actually helps you keep length.
- Build a gentle routine with the Hair Routine Builder.
- Repair breakage with our Dry & Damaged Hair Guide.
- Check your overall condition with the Hair Health Score Calculator.
- Wondering what’s normal? See how fast hair grows per week, month and year in our How Fast Does Hair Grow? guide.
Frequently Asked Questions
How fast does hair grow?
On average, hair grows about half an inch (1.25 cm) per month, roughly 6 inches (15 cm) a year. Individual rates vary with genetics, age, health, and nutrition, commonly falling between about 0.3 and 0.7 inches (0.8 to 1.8 cm) per month.
How does the hair growth calculator work?
You enter your current length, goal length, and growth rate. The calculator divides the length you need to gain by your monthly rate to estimate how many months it will take, then shows a target date and month-by-month checkpoints.
Can I make my hair grow faster?
Not significantly, since growth speed is largely genetic. What you can do is support healthy growth with good nutrition, a healthy scalp, and gentle handling, and avoid breakage, which is often why hair seems to stop growing.
Why isn’t my hair getting longer?
Most of the time hair is growing but breaking at the ends as fast as it grows, so you don’t retain the length. Reducing heat, detangling gently, keeping ends moisturized, and protecting hair at night all help you keep the length you grow.
Does trimming hair make it grow faster?
No, trimming doesn’t speed up growth because hair grows from the follicle at the scalp. But trimming off split ends prevents damage from traveling up the strand, which helps you retain length over time.
Does curl type affect how long my hair looks?
Yes. Curly and coily hair shrinks as it dries, so it can look much shorter than its true length. For accurate tracking, measure your hair stretched out, and use the same method each time so your results stay comparable.
How accurate is a hair growth calculator?
It’s an estimate, not a guarantee. Real growth varies month to month and depends on genetics, health, and breakage. Use it as a planning guide, and adjust the growth rate based on what you actually measure over a few months. Use the same measuring method each time