Eyebrow Ruler & Brow Mapping String: How to Use Them

Mapping freehand is possible, but results vary from treatment to treatment and you often spend longer correcting. With a ruler and a mapping string you use the same method for every client. That gives you symmetrical brows, a crisp outline for henna and hybrid brow tint, and a shape you can repeat exactly next time. For the full step-by-step method for the start, arch and tail, see our brow mapping tutorial; this article focuses on the tools themselves.

What does the eyebrow ruler do?

The Eyebrow Ruler is a self-adhesive disposable ruler with an accurate scale. You stick it on the forehead, above the brows, where it stays put without slipping, leaving both hands free to measure and mark. The scale lets you read the same distances on the left and right, so both brows match. The ruler is soft and flexible and follows the shape of the forehead.

Each pack contains 50 rulers. Use one per client and discard it afterwards.

What does the brow mapping string do?

The Brow Mapping String is a pre-coloured bamboo thread, 10 metres per pack. You pull a short length taut, place it along the points and press it against the skin. The pigment leaves a straight, clearly visible line. In seconds you can mark the vertical lines through the start, arch and tail, plus the top and bottom lines of the brow.

The string is vegan, dermatologically tested and available in black and white. The set includes both colours and 10 latex finger cots. Wear gloves or use the finger cots: the pigment transfers onto your fingers.

Black or white mapping string?

Choose for contrast. White string shows up best on darker skin or dark brows; black string on fair skin or blonde brows. A line that stands out works faster and more accurately than one you have to search for.

How to use the brow mapping string and ruler together

Step 1 — Apply the ruler

Cleanse and degrease the forehead and brows. Stick the ruler straight above the brows, with the centre of the scale above the centre of the nose.

Step 2 — Find the start, arch and tail

Measure from the nostril wing: straight up for the start, past the outer edge of the iris for the arch and to the outer corner of the eye for the tail. Read off where the points sit on the ruler on both sides and mark them with the White Stick. If one eye sits noticeably higher, work one side at a time; see brow mapping for asymmetrical faces.

Step 3 — Draw the lines with the string

Use the string to mark vertical lines through the three points. Then draw the top and bottom lines of the brow to complete the shape. Work with a short, taut length of thread: it gives the sharpest line.

Step 4 — Check and protect

Let your client look in the mirror and adjust the line where needed. If you work with henna or hybrid brow tint, apply highlighting paste or the White Stick to the skin around the shape. Then remove the ruler and start the treatment.

Working hygienically

The ruler is single-use: one per client, then discard. Cut a fresh length of string for every client too, so nothing passes from one client to the next. Clients also see that you measure with a fixed, professional method rather than by eye.

Which treatments are they for?

You use the ruler and string for almost every brow treatment: shaping before tweezing, waxing or threading; tinting with henna, hybrid or classic brow tint; brow lamination; and as preparation for microblading and powder brows. They make the biggest difference with henna and Hybrid Brows: there you colour the skin as well, so any deviation in the line is immediately visible. You'll find tinting techniques in the Henna Brows Academy and the Hybrid Brows Academy.

Frequently asked questions