Hair growth progress photos that can actually be compared

The reason people cannot tell whether their routine is working is not that hair is mysterious. It is that hair changes at about a centimetre a month, and human visual memory over that timescale is close to worthless.

You look in the mirror every day. Each day is imperceptibly different from the last, and your sense of "before" is not a record — it is a reconstruction, heavily influenced by how you feel today. This is precisely the gap a photograph fills, and it only fills it if the photographs are comparable.

The five variables

Almost every useless hair comparison fails on at least one of these.

Light. The single biggest source of false differences. Overhead bathroom light creates scalp shadows that read as thinning; window light at midday flattens them out. Different colour temperatures make the same hair look dull or shiny.

Fix: the same location, the same light source, at roughly the same time of day. Indirect natural light from a window is ideal. Never use a mix of window light and a ceiling lamp, because the mix changes with the weather.

Distance and angle. Phone cameras distort with distance, and a five-degree difference in head tilt changes how much scalp is visible at a part more than a month of growth does.

Fix: the same distance — mark a spot on the floor — and the same framing. Prop the phone rather than holding it out, and use the volume button or a timer.

Hair state. Freshly washed hair, day-three hair, product-heavy hair and air-dried hair look like four different heads.

Fix: pick one state and always use it. The most repeatable is dry, on the same day of your wash cycle, with no styling product.

The section. For density, the part line is the standard because it exposes scalp reliably. For length, the ends. For a hairline, the temples.

Fix: part in the same place every time, using a comb and a mirror rather than your fingers, and photograph the same defined area.

Scale. A photo of hair with nothing else in frame has no scale, so length changes are invisible.

Fix: include a fixed body landmark — a shoulder, a collarbone, a specific top — or hold a tape measure alongside a section.

A setup for hair growth progress photos, in two minutes

1. Choose your spot: a wall by a window, indirect light, no overhead lamp on.
2. Mark where you stand. Tape on the floor, or a specific floor tile.
3. Prop your phone at a fixed height. A shelf, a stack of books, a small tripod.
4. Take four shots each time: the part line from directly above, the front hairline, the back of the head, and a full-length side view with a shoulder in frame.
5. Wear the same or a similar top. Colour affects both the light bouncing onto your hair and your perception of it.
6. Note the date and the day of your wash cycle.

Then leave it for a month. This is the hard part.

Reading them without fooling yourself

Compare the same shot type only. Part to part, hairline to hairline. Never compare a part photo with a general shot.

Look at the earliest and latest, not the sequence. Scrolling through twelve monthly photos gives you the same problem as the mirror — each is barely different from its neighbour. Put month one and month twelve side by side.

Expect noise. Humidity, the day of your cycle, how you slept and whether you have just brushed all produce visible differences with no underlying change. Two photos three months apart carry a signal; two a week apart mostly carry weather.

Be honest about the light. If one photo is brighter, you cannot conclude anything about density from it. Take it again rather than reasoning around it.

What to expect on the timeline

At about a centimetre a month, which is what hair actually does:

• One month: nothing visible. Do not evaluate anything.
• Three months: roughly 3–4 cm. Visible in a length photo with a scale reference. This is the earliest meaningful check-in for any routine change, and it matches the growth cycle's own timescale.
• Six months: 6–8 cm. Obvious in photos, and long enough that a density change from regrowth after shedding starts to show.
• Twelve months: 12–15 cm. The comparison that changes people's minds about whether their routine works.

For shedding rather than length, the timeline is different: photograph the part every two weeks, because during a shed the useful question is whether density is stabilising, and that resolves faster.

Why bother

Because it converts an anxious, unanswerable question — is this getting worse? — into a thing you can check. A great many people who are convinced they are losing hair are not, and a photograph from three months ago is the only argument that ever settles it.

It is also the only way to evaluate a change honestly. Adopt one change, hold everything else still, photograph at zero and three months, and you have a real answer instead of a feeling. Doing that consistently is more work than most people will sustain by hand, which is why our app does the reminding, the standardising and the side-by-side comparison for you — but the method above is the whole of it, and it works just as well with a phone and a piece of tape on the floor.