track your journey

Length Retention Challenge Tracker

Track a 90-day hair growth challenge: log monthly measurements in five zones, check in when you stick to your routine and see how much length you really keep.

Saved only in this browser — nothing is uploaded.

Date measured

Stretched length from the scalp, by zone

Front (hairline)

Crown

Nape

Left side

Right side

How to measure each zone

Front (hairline): Part a small section at the center of your hairline, stretch it forward and down over your face, and measure from the hairline to the ends.
Crown: Take a section at the top of your head, stretch it straight back and down, and measure from the scalp to the ends.
Nape: At the center of the nape (lowest hairline at the back), stretch a section downward and measure from the scalp to the ends.
Left side: Above the left ear, stretch a section straight down and measure from the scalp to the ends.
Right side: Same as the left, above the right ear — comparing the two shows uneven breakage.
Use a soft tape measure, stretch the section gently (not pulled tight) and measure on the same day each month, ideally on clean, dry hair.

Note (optional)

E.g. trimmed ½″, started a new leave-in, braids taken down.

How to use the Length Retention Challenge Tracker

Measure five zones and tap “Save measurement”

In the Measure tab, enter the stretched length from the scalp to the ends at the front, crown, nape, left and right side. Open “How to measure each zone” if you’re unsure where to measure.
Repeat once a month

Measure the same spots on the same day each month. “Copy last measurement” fills in last month’s numbers so you only change what grew.
Check your progress

The Progress tab shows your latest average, total change and growth rate per month, plus a chart of every zone so you can spot an area that keeps breaking.
Check in and start the 90-day challenge

Tap “I stuck to my routine today” to build a streak, then start the 90-day challenge. Finish it to download a certificate.
Export a backup

Your data lives only in this browser. Use “Export backup” in the Backup tab to keep a copy or move it to another phone.

How to use the Length Retention Challenge Tracker (61 s)

How the hair growth challenge tracker works

Hair can grow steadily at the scalp while the ends break off just as fast, so the mirror shows no change. This tracker separates the two by measuring what you actually keep. Use it on its own or as the scoreboard for a 90-day hair growth challenge.

1. Five zones, measured stretched

Each entry records the stretched length from the scalp to the ends at the front hairline, crown, nape and both sides. Zones break at different rates — the nape meets collars and pillows, the edges carry the tension of tight styles — so a single number can hide a problem area. The average of the five zones gives your overall trend; the dashed lines on the chart show each zone on its own.

2. Growth per month

Between two entries, the change in length is divided by the time between them (an average month is 30.44 days). Your headline growth rate is the trend line across all of your entries, which smooths out the odd high or low measurement. It appears once your entries span at least three weeks, because shorter gaps are mostly measuring noise. A negative change usually means a trim or breakage — add a note so you remember which.

3. Check-ins and streaks

Retention depends on what you do every day: gentle detangling, protecting your ends at night, going easy on heat. Tap the check-in button on days you follow your routine. Your current streak counts back from today, and stays alive until the end of the day after your last check-in, so you don’t lose it just because you haven’t checked in yet this morning.

4. The 90-day challenge

Pick a start date and the tracker counts the days, marks milestones at days 30, 60 and 90, and compares your average length at the start with your latest measurement inside the challenge window. When day 90 arrives, you can download a certificate with your check-ins and length change.

Your data stays with you

Everything is stored in your browser’s local storage on this device — no account and nothing uploaded. Export a backup file to keep a copy or to move your tracker to a new phone. The file format is also what our upcoming Hair Journal will import.

The five measuring zones

Zone	How to measure	What a lagging zone can point to
Front (hairline)	Stretch a center section forward over the face; measure hairline to ends.	Short, thinning or broken edges. Tight ponytails, braids and glued wigs pull here most.
Crown	Stretch a top section straight back; measure scalp to ends.	Usually the longest zone. A crown that lags can point to heat or color damage concentrated on top.
Nape	Stretch the lowest back section downward; measure scalp to ends.	Friction from collars, scarves, seat backs and cotton pillowcases. Fragile, dry ends tangle here first.
Left side	Stretch a section above the left ear straight down; measure scalp to ends.	Compare with the right side: the side you sleep on or part toward often breaks more.
Right side	Same as the left, above the right ear.	A steady gap between sides is more telling than one low month.

Measure on clean, dry hair, gently stretched — not pulled tight — on the same day each month. Thinning patches or scalp pain are a reason to see a dermatologist, not to measure harder.

Frequently asked questions

What is a hair growth challenge?

A hair growth challenge is a set period — often 90 days — where you follow a consistent, gentle routine and measure your length at the start and end. It does not make hair grow faster; it helps you keep more of the length you grow by cutting down on breakage, and the measurements show whether your routine is working.

How do I measure hair growth accurately?

Measure the same five spots every time, on clean, dry hair, gently stretched from the scalp to the ends with a soft tape measure. Use the same day of the month and the same method. Small changes of a tenth or two of an inch are often measuring error, so trust the trend over several months.

How often should I measure my hair?

Once a month is enough. Hair grows slowly, so weekly measurements mostly show noise. For a 90-day challenge, measure on day 1 and around days 30, 60 and 90.

How much hair growth is normal in 90 days?

Half an inch a month is the figure most people quote, which would be about 1.5 inches in 90 days. A study of African hair measured a slower average — roughly 0.3 inches a month, or about 0.9 inches in 90 days — and individual rates vary widely. What you keep also depends on breakage, which is why the tracker measures length rather than assuming a rate.

Why is one section of my hair shorter than the rest?

Different zones face different stress. The nape rubs against collars and pillows, the edges take the most tension from tight styles, and the side you sleep on can break more. If a zone keeps getting shorter, look at what touches or pulls that area. Thinning edges, bald patches or a sore scalp are a reason to see a dermatologist.

Is my tracker data private?

Yes. Measurements, check-ins and your challenge are saved only in this browser on this device. Nothing is sent to our servers. That also means clearing your browser data deletes it — export a backup file regularly.

Can I move my tracker to another phone?

Yes. Open the Backup tab, export the .json file, send it to your other device and import it there. Importing merges with anything already on that device.