You’ve found the perfect shade - maybe a soft hazel for everyday glow or a bold grey for a full switch-up - and then you spot one detail on the product page: power. If you’re wondering what does power mean for coloured contacts, the short answer is simple. Power (also called grade) refers to the prescription strength in the lens, which helps correct your vision while you wear coloured contacts.
That means coloured lenses are not only about changing your eye colour. They can also help you see clearly, as long as you choose the right prescription. For anyone who wants style and practicality in one, understanding power is the key to shopping smarter.
What does power mean for coloured contacts?
Power is the number that shows how much vision correction a contact lens provides. You’ll usually see it written with a minus sign or a plus sign, such as -2.00 or +1.50.
If your power starts with a minus sign, that usually means the lens is correcting short-sightedness, also called myopia. If it has a plus sign, it is usually correcting long-sightedness, or hyperopia. The further the number is from zero, the stronger the correction.
So if you wear glasses or contact lenses already, your power is one of the main details from your prescription that you need to match when buying coloured contacts with vision correction. If you do not need help seeing at distance or close up, you would normally choose plano lenses instead. Plano simply means non-prescription.
Why power matters when buying coloured lenses
Style comes first for a lot of coloured contact shoppers, and that makes sense. You’re choosing a look. But if the power is wrong, even the most flattering lens can end up feeling like a bad buy.
A lens with the right power helps you see comfortably while enjoying the colour effect you want. A lens with the wrong power can leave your vision blurry, strained or just slightly off, which is often more noticeable than people expect. Even a small mismatch can make daily wear frustrating.
This matters even more if you plan to wear your coloured contacts for outings, work, events or content days when you want to look good and feel comfortable for hours. Beauty works better when you are not squinting.
Power is not the same as colour, size or effect
One easy mistake is thinking power changes the appearance of the lens. It does not. The colour, pattern and design create the visual result. Power only affects vision correction.
So if you are choosing between brown, olive, black or doll-eye styles, the power will not make one lens look more dramatic than another. A -3.00 lens in grey and a plano lens in the same design should look the same cosmetically, assuming all the other lens details are identical.
This is good news if you need prescription lenses but still want full freedom with your look. You do not have to give up style just because you need corrective power.
How to read the power on your prescription
If you have had an eye test, your prescription will usually include several numbers and abbreviations. The power may be listed as SPH, which stands for sphere. This is the number most standard coloured prescription contacts use.
If your prescription says something like -1.25 in one eye and -1.75 in the other, that means each eye needs a different power. In that case, you should order the correct power for each eye rather than assuming they are the same.
Some people also have CYL and AXIS values on their prescription. These relate to astigmatism. Not all coloured contact lenses are made to correct astigmatism, so this is one of those situations where it depends on your exact prescription and the type of lens available. If your prescription includes more than sphere power, it is worth checking carefully whether a standard coloured lens is suitable for you.
What if your glasses power and contact lens power are different?
This catches a lot of people out. Your glasses prescription is not always exactly the same as your contact lens prescription.
For lower prescriptions, the difference may be very small or not matter much. For stronger prescriptions, though, contact lens power can differ because the lens sits directly on the eye, while glasses sit a short distance in front of it. That changes how the prescription works.
So if you only know your glasses prescription and you are buying coloured contacts for the first time, do not assume it will match perfectly. The safest option is to use a current contact lens prescription or get advice from your optician.
Do you need power in both eyes?
Not always. Some people have the same prescription in both eyes, some have different powers, and some only need correction in one eye.
That means your order should reflect your actual prescription, not what feels easiest to select. If you choose the same power for both eyes when your prescription is different, your vision may feel uneven. If one eye does not need power, you may need one prescription lens and one plano lens, depending on the product options.
It can feel fiddly the first time, but getting each eye right makes a real difference to comfort and clarity.
What if you do not need vision correction?
If you want coloured contacts only for the look, you do not need power. In that case, you would choose plano lenses. These give you the style effect without prescription correction.
This is especially popular if you like switching eye colours to match makeup, outfits or different moods. It keeps things simple while still giving you that beauty upgrade. If your vision is already fine, adding power when you do not need it can make your sight worse, not better.
Can the wrong power make coloured contacts uncomfortable?
Yes, although people often describe it as odd vision rather than physical discomfort at first. The wrong power can cause blur, headaches, eye strain or a sense that your eyes are working too hard.
That is different from fit-related discomfort, which usually comes from lens size, material or how the lens sits on the eye. Power does not control the fit. Still, if your vision feels off, the whole wearing experience can seem uncomfortable even if the lens itself fits properly.
This is why shopping by colour alone is not enough when you need prescription contacts. The best pair should give you the look you want and the clarity you need.
What does power mean for coloured contacts if you shop online?
Online shopping makes it much easier to browse by shade, finish and vibe, but it also means you need to know your prescription details before you add to basket. Power is one of the most important fields to get right.
When you are shopping online, double-check the number, the plus or minus sign, and whether each eye needs a different option. A tiny mistake can mean your order looks amazing but does not work for day-to-day wear.
If you are shopping with a style-led brand like PRISMATA, the good part is that you do not have to choose between fashion and function. You can go for the colour story you love and still select a power that suits your eyes.
A few common mistakes to avoid
The biggest mistake is guessing your power. If you have not had a recent eye test, it is easy to rely on memory or old packaging, but prescriptions can change. Another common mistake is ordering your friend’s favourite lens without checking whether the available power matches your own needs.
It is also worth paying attention to the sign in front of the number. -2.00 and +2.00 are completely different prescriptions. Mixing them up is a fast way to end up with unusable lenses.
And if one eye is weaker than the other, do not round both eyes to the same number just to keep things simple. Your eyes will notice.
Choosing coloured contacts with confidence
Once you understand power, shopping becomes much easier. You can focus on the fun part - choosing between natural enhancement, statement eyes or an enlarging doll-eye effect - while knowing the practical side is covered too.
The best coloured contacts should feel like an easy upgrade. They should suit your style, support clear vision if you need correction, and fit naturally into your routine without second-guessing every number on the page.
If you are ever unsure, pause before you buy and check your latest prescription. Getting the right power is not the glamorous part of choosing coloured contacts, but it is what lets the glamorous part work properly.