You’ve decided to try colored contacts, and your eye doctor says the next step is a “fitting.” If you’ve never had one, you might be wondering what actually happens — and whether it’s worth the appointment.
A contact lens fitting is a short, painless exam that determines the exact lens measurements your eyes need. It’s not optional — it’s the step that separates comfortable, safe lenses from lenses that scratch, blur, or worse. And once you know what happens, it’s a lot less intimidating than it sounds.
This guide walks you through a contact lens fitting from start to finish, so you know exactly what to expect.
Why a Fitting Is Non-Negotiable
Contact lenses sit directly on your cornea, so they need to match the unique shape of your eye. Two measurements matter most:
- Base curve — the curvature of the lens, which must match the curve of your eye so the lens sits correctly without being too tight or too loose
- Diameter — the width of the lens, which must cover your cornea properly without irritating the edges
A lens with the wrong base curve can fit too tightly — reducing oxygen to your cornea — or too loosely, moving around and scratching your eye. Neither is something you want to discover on your own.
Step 1: The Eye Health Exam
Before any measurements, your provider checks the overall health of your eyes. They’ll look for:
- Signs of dry eye, which affects lens comfort
- Any corneal irregularities that could complicate lens wear
- General eye health issues that might make contacts unsuitable
This step catches problems early — and ensures contacts are actually a good choice for you.
Step 2: Measuring Your Eye
Next comes the measuring. Using a device called a keratometer or a corneal topographer, your provider measures the curvature of your cornea. This gives them the base curve your lenses need.
They’ll also assess the size and shape of your eye to determine the right diameter. These are quick, non-contact measurements — you’ll simply look into a machine while it takes readings.
Step 3: Determining Your Prescription
If you need vision correction, your provider converts your glasses prescription into a contact lens prescription. As a reminder, these numbers differ because contacts sit directly on your eye, closer than glasses.
If you don’t need vision correction, your prescription will be “plano” (0.00), and the colored lenses are purely cosmetic — but the fitting and prescription are still required by law.
Step 4: Trying On a Trial Lens
This is where it gets hands-on. Your provider places a trial lens on your eye — usually a clear diagnostic lens with the right measurements — to verify:
- The lens moves slightly when you blink (a sign of a healthy fit)
- Your vision is clear with the lens in place
- The lens is comfortable
They’ll examine the lens on your eye under a slit lamp, checking that it’s centered and moving properly. If it doesn’t fit right, they’ll try a different base curve or diameter until it does.
Step 5: Learning Insertion and Removal
If you’re new to contacts, your provider will teach you how to put lenses in and take them out. This usually involves:
- Washing and drying your hands thoroughly
- Placing the lens on the tip of your finger
- Holding your eyelids open gently
- Looking up and placing the lens onto your eye
Don’t worry if it takes a few tries — everyone struggles the first time, and your provider will guide you through it until you’re comfortable.
Step 6: Getting Your Prescription
Once everything checks out, you’ll receive your contact lens prescription, which includes:
| Measurement | What It Tells You |
|---|---|
| Base Curve (BC) | The curvature of the lens your eye needs |
| Diameter (DIA) | The width of the lens |
| Power / Sphere | Your vision correction, or 0.00 for plano |
| Brand / Material | The specific lens your provider prescribed |
You can then use this prescription to order colored contacts — including the color and style you want — as long as the base curve, diameter, and material match what was prescribed.
How Often Do You Need a New Fitting?
A contact lens prescription is typically valid for one year. After that, you’ll need a new fitting and exam, because:
- Your eyes change over time, even subtly
- Your provider needs to check for early signs of contact-related problems
- An outdated prescription can lead to discomfort and eye strain
Even if your lenses feel fine, annual checkups are how problems get caught before they become serious.
Frequently Asked Questions
Does a contact lens fitting hurt?
No. The measurements are non-contact, and the trial lens is soft and comfortable. The only part that might feel unusual is the sensation of a lens on your eye for the first time — which is more strange than painful.
How long does a contact lens fitting take?
Typically 30 to 60 minutes, including the eye health exam, measurements, trial lens, and insertion practice. If it’s your first time, allow a little longer for the hands-on training.
Do I need a fitting for colored contacts with no vision correction?
Yes. Even plano colored contacts require a fitting and prescription. The base curve and diameter still need to match your eye, and the law requires a prescription for all contact lenses regardless of whether they correct vision.
Can I use my glasses prescription to order contacts?
No. Contact lens and glasses prescriptions are different. You need a separate contact lens fitting to determine your base curve, diameter, and contact lens power.
How much does a contact lens fitting cost?
Costs vary by provider and location, and may or may not be covered by insurance. Many providers bundle the fitting with a comprehensive eye exam. Ask about the cost when you schedule.
What if the trial lens feels uncomfortable?
Tell your provider immediately. Discomfort during the trial is exactly what the fitting is designed to catch. They can adjust the base curve, diameter, or material until they find a lens that fits comfortably.
Can I get fitted for colored contacts and regular contacts at the same time?
Yes. The fitting determines your eye’s measurements, which apply to both colored and clear lenses as long as the base curve and diameter match. Your provider can help you choose appropriate options for both.
The Fitting Is the Foundation
A contact lens fitting might feel like an extra step, but it’s the difference between lenses that disappear into your day and lenses you’re constantly aware of. Get fitted once, do it properly, and every pair of colored contacts you wear after that is built on a foundation of comfort and safety.
Ready to get started? Browse our colored contact collection to see your options, then schedule a fitting with your eye care provider.