If the numbers and letters on a lash box look like a secret code, you’re not alone. J, B, C, D, L—and measurements in millimeters. I remember my first pair said “D250” and I had no idea if that meant my lashes would look like paintbrushes or spider legs. Spoiler: they looked like spider legs.

Here’s the simple, step-by-step way to choose the right lash curl for your eyes—and never guess again.

WHAT THE NUMBERS ON LASH BOXES MEAN

Lash curls are labeled with letters. The letter tells you how much upward bend the lash has:

• J curl — the most natural, with barely any lift.
• B curl — a subtle curve that adds a hint of lift.
• C curl — the classic lift that makes eyes look awake.
• D curl — a dramatic curve, great for photo-ready looks.
• L curl — a sharp 90-degree kind of lift, made for deep-set eyes.

The number (like 0.10, 0.15, 0.20) is the thickness of the fiber, not the curl. Bigger numbers mean thicker lashes.

HOW TO MATCH CURL TO EYE SHAPE

• Round eyes: C curl works best. It lifts without overwhelming the eye.
• Almond eyes: B or C curl gives a flattering lift.
• Hooded eyes: B or C curl helps avoid pressing into the crease.
• Deep-set eyes: L curl or a strong D curl opens the eye and prevents the lash from disappearing.
• Monolid eyes: A C curl that angles upward can add the illusion of an eye crease.

When in doubt, C curl is the safest starting point. It’s the most universally flattering for 80% of eye shapes.

THE 30-SECOND CURL TEST

Hold the lash against your lash line before putting any adhesive on it. Look straight ahead. If the lash tip points upward and away from your eye, it’s a good match. If it points into your skin or sticks straight out, try another curl.

This simple test takes 30 seconds and has saved me from hundreds of bad lash days.

LASH CURL FAQ, ANSWERED

Is a C or D curl more natural?

C curl is more natural. D curl gives a more doll-like, dramatic look. If in doubt, start with C.

Can I curl false lashes with an eyelash curler?

No, that will damage the fibers. Choose the right curl at the store, and you won’t need to curl them yourself.

THE CURL I PICK FOR EVERY CLIENT

After all these years, the most forgiving curl is C. It opens the eye, flatters most shapes, and feels barely-there. PHANSTA LASHES designs nearly every style with a C curl, and I’ve never had a client say they wished they’d picked something less dramatic. It’s the “stand out without shouting” sweet spot.

Find Your C Curl Lash at PHANSTA

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