Free buying tool
Contact lens case size finder
Not sure whether you need a Small, Medium, or Large case? Answer three quick questions and get a clear recommendation for your routine, with capacity by size and a direct link to buy. It runs entirely in your browser.
Find your case size
Answer three quick questions and we will recommend the right Sturdysight case size for your routine. Everything is calculated in your browser. Nothing is uploaded.
For daily disposables, each day uses one fresh pair. Pick how many days you want staged at once.
A balanced everyday size.
Your recommended size
Best match
Medium
Holds 30–40 days of daily lenses per case, 2-pack included.
- You want to keep about 30 days of daily lenses in one case, which fits the Medium capacity of 30–40 days.
- Medium is our most popular size and the safe default when you are unsure, because it fits every brand guaranteed.
Compare all three sizes
| Size | Holds | Covers your 30 days? |
|---|---|---|
| Small | 20–30 days | Yes |
| MediumYour pick | 30–40 days | Yes |
| Large | 60–90 days | Yes |
Every Sturdysight case ships as a labeled, waterproof 2-pack, so a smaller size can still cover a longer stretch across both cases.
Capacities are approximate and vary by lens brand and blister size. Medium is sized to hold at least 30 lenses for every brand. When in doubt, size up.
What size contact lens case do you need?
Choosing a contact lens case size sounds like it should be obvious, but it trips up more people than you would expect. The reason is that the right size has almost nothing to do with how many lenses exist in the world and everything to do with how many you personally keep staged at once. A daily disposable wearer who carries a week at a time has a completely different need from someone who buys a full year and wants to stock a quarter in one place. Both can be wearing the exact same lenses. The case size that fits each of them is different, and that is the whole problem the finder above is built to solve.
Start with the number that actually matters: how many days of supply you want to live in the case. For daily disposables, one day of wear uses one fresh pair, so a month of supply is about thirty pairs. If you only ever carry a week or two, you do not need a case built to hold ninety days. If you genuinely want to stage a quarter at home so you refill less often, a small case will leave you topping it up constantly. The finder asks you this directly, then maps your answer to the capacity range of each size so you are choosing on real numbers rather than a guess at a store shelf.
The second factor is how you use the case day to day. A case that lives in a carry-on or a jacket pocket should be picked for footprint first, which is where Small wins even when its capacity is more than you strictly need. A case that sits on a bathroom shelf at home can be larger without any downside, so stock-up routines lean toward Large. Most people fall in the middle and want one case that handles both a normal month and the occasional trip, and that is exactly the everyday Medium use case. The third factor, brand fit, matters because lens and blister sizes are not identical across brands, so a guaranteed-fit size removes the risk of a case that is a little too tight for the brand you actually wear.
| Size | Holds | Best for |
|---|---|---|
| Small | 20 to 30 days | Travel kits, a single trip, or a compact bag you carry every day. The smallest footprint of the three. |
| Medium | 30 to 40 days | The everyday default. Holds at least 30 lenses for every brand, so it is the safe pick when you are unsure. |
| Large | 60 to 90 days | Stocking up for a full quarter so you refill less often, or staging a long supply at home. |
How many contact lenses fit in each case
The honest answer to how many lenses fit in a case is that it depends on your brand, because lens and blister geometry differ from one manufacturer to the next. A thin daily lens packs differently from a thicker toric or multifocal, and that changes how many you can comfortably stage without crowding. That is why a single hard number can be misleading. What is reliable is the working range each size is designed around, and the guarantee that the Medium size holds at least thirty lenses for every brand on the market, which is the figure you can lean on when you are not sure how your particular lenses pack.
As a practical guide, the Small case stages roughly twenty to thirty days of daily lenses, which is about a month for most people and plenty for a trip. The Medium case stages thirty to forty days, enough for a comfortable month with headroom, and it is the size most wearers settle on because it never feels tight regardless of brand. The Large case stages sixty to ninety days, a full quarter, which is the sweet spot for anyone who buys in bulk and wants to refill the case as rarely as possible. Those ranges are what the finder uses to check whether a given size covers the number of days you told it you want to keep on hand.
One detail that changes the math in your favor is that every Sturdysight size ships as a 2-pack. Two cases mean you can split a longer supply across both, keep one in a travel bag and one at home, or set up his-and-hers cases for a couple. So when the finder shows that a single Small case covers thirty days, remember that the pack actually gives you two cases to work with. This is why the comparison table reports capacity per case while reminding you that the pack doubles your real flexibility, and it is one more reason most people do not need to jump to the largest size to get the coverage they want.
If you wear reusable lenses, the counting works differently because those lenses are not staged as sealed pairs. Bi-weekly and monthly lenses soak overnight in solution in a standard two-well case, one well per eye, and they are replaced on a schedule rather than stocked in quantity. In that situation, the organizer is for spares and travel rather than your nightly storage, and a Small size is usually all you need. The size finder is built around the daily disposable use case because that is what the Sturdysight organizer is designed for, so if your routine is reusable lenses, treat the recommendation as guidance for your spare and travel supply.
Small vs Medium vs Large, in plain terms
If you want the one-line version, here it is. Choose Small when space is the priority and you carry a modest supply, typically for travel or a daily bag. Choose Medium when you want one dependable case for everyday life that fits any brand and covers a comfortable month. Choose Large when you stock up and want the fewest possible refills, staging a full quarter at home. Almost everyone fits cleanly into one of those three sentences, and the finder simply confirms which one is you.
The trap people fall into is treating the decision as a contest where bigger automatically wins. It does not. A Large case stocked with two weeks of lenses is mostly empty plastic taking up space, and a Small case asked to hold a quarter forces constant refilling. The best case is the smallest one that comfortably holds the supply you actually keep staged. That framing keeps your bag light, your shelf tidy, and your money spent on the size you will genuinely use, which is the entire point of choosing deliberately instead of grabbing the biggest box.
Because all three sizes share the same labeled, waterproof, high-strength build and the same 2-pack format, you are never trading away durability or organization by picking a smaller size. The left and right labeling, the watertight seal, and the rugged shell are identical across the lineup. The only variable is capacity. That makes the choice refreshingly simple: decide how much supply you want to live in the case, factor in travel and brand fit, and let those answers point you to a size. The finder does that math for you and links you straight to the right product.
Five sizing mistakes to avoid
Most sizing regrets come from a handful of avoidable habits. Steer clear of these and you will land on the right case the first time.
Buying the biggest case by default
A Large case is great for stocking up, but if you mostly travel it is bulkier than you need and rides around half empty. Match the size to how much supply you actually keep staged at once, not to the largest number on the shelf.
Sizing for lenses you do not stage
If you wear daily disposables but only ever carry a week at a time, you do not need a quarter of capacity. Size for the supply that lives in the case, and reorder or refill the case from your main box as you go.
Forgetting it is a 2-pack
Every Sturdysight size ships as two cases. A Small 2-pack can cover a longer stretch than the single-case number suggests, because you can split your supply or keep one case at home and one in a bag.
Ignoring brand fit
Blister and lens sizes vary by brand. A case that fits one brand snugly can be tight for another. Medium is sized to hold at least 30 lenses for every brand, which is why it is the guaranteed-fit choice if you switch brands.
Confusing a staging case with a soaking case
The Sturdysight case organizes sealed daily disposable pairs. If you wear reusable bi-weekly or monthly lenses that soak in solution overnight, you still need a standard two-well soaking case for nightly storage, and you can use a Small organizer for spares and travel.
Sizing for travel and on the go
Travel is the one situation where the usual logic flips. At home, capacity is the deciding factor and footprint barely matters because the case sits on a shelf. On the road, footprint is everything. Every cubic inch in a carry-on or a toiletry bag is contested, and a case that takes up half the room of a larger one is worth more than a few extra days of capacity you will not use on a short trip. That is why the finder steers travel-first routines toward the Small case even when a Medium would technically hold a bit more.
The 2-pack format makes travel sizing easier than it first appears. You can keep one case permanently in your travel bag, already stocked, and the second at home as your everyday case. When a trip comes up you grab a bag that is already packed for your eyes, which removes one more thing from the pre-trip scramble. For longer trips where you would rather carry everything in a single case, a Medium covers about a month without becoming bulky, so it remains a sensible travel size for anyone who prefers one case over two.
A quick word on flights and airport security. Sealed daily disposable lenses in their original blisters are not liquids, so a case of staged pairs is not subject to the liquid rules. The solution and rewetting drops you carry are, so keep those within the standard travel-size liquid limits and in your clear bag. The case itself is just an organizer for your lenses, which is exactly why a compact, waterproof, clearly labeled case is such a relief to travel with. Pair the right size with our replacement and reorder tools and your eyes are handled before you have even finished packing.
Frequently asked questions
What size contact lens case do I need?
It comes down to how many days of daily disposable lenses you want to keep staged in one case. Small holds about 20 to 30 days and suits travel and compact bags. Medium holds about 30 to 40 days and is the safe everyday default because it fits at least 30 lenses for every brand. Large holds about 60 to 90 days for people who stock up a full quarter at a time. If you are unsure, Medium is the recommended starting point. The size finder above turns your routine into a specific recommendation in seconds.
How many contact lenses fit in a case?
It depends on the case size and your lens brand, because blister and lens sizes vary. As a working guide, the Small Sturdysight case holds roughly 20 to 30 days of daily lenses, Medium holds 30 to 40 days, and Large holds 60 to 90 days. Medium is specifically sized to hold at least 30 lenses for every brand on the market, so it is the dependable choice if you switch brands or are not sure how your lenses pack. Each size ships as a 2-pack, so the total you can stage across both cases is higher than the single-case figure.
What is the difference between small, medium, and large contact lens cases?
The difference is capacity and footprint. Small is the most compact and carries about 20 to 30 days of daily lenses, which is ideal for travel or a daily bag. Medium is the most popular size, carries 30 to 40 days, and is guaranteed to hold at least 30 lenses for any brand, making it the best all-around pick. Large carries 60 to 90 days, so you can stock up for an entire quarter and refill the case far less often. All three are the same labeled, waterproof, high-strength 2-pack design, so the only thing changing is how much supply each case holds.
Should I size up or size down if I am between sizes?
Size up. A slightly larger case costs the same to carry and gives you headroom if you travel longer than planned, switch to a bulkier brand, or want to stage a few extra pairs. A case that is too small forces you to refill more often or leave pairs out of the case, which defeats the purpose of organizing them. The one exception is travel, where the Small case wins purely on how little space it takes up. The finder accounts for this and nudges you to the safer size automatically.
Which case size is best for travel?
For most trips, the Small case is best because it takes up the least room in a carry-on, toiletry bag, or pocket while still staging about 20 to 30 days of daily lenses. Since it is a 2-pack, you can keep one case in your bag and one at home, or split a longer supply across both. If you switch brands often or want a single case guaranteed to fit any brand, Medium is a small step up in size and still travel-friendly. For a longer trip where you want everything in one place, Medium covers about a month.
Does case size matter for monthly or bi-weekly lenses?
The Sturdysight case is built to organize sealed daily disposable pairs, so the sizing above is for daily lenses. If you wear reusable bi-weekly or monthly lenses, you store them overnight in a standard two-well soaking case with solution, not in an organizer. Many reusable-lens wearers still keep a Small organizer for spare sealed pairs, travel backups, or a partner's lenses. If your routine is a mix, choose the organizer size for the daily-disposable spares you carry, and keep a dedicated soaking case for your reusable lenses.
How does the case size finder work?
You answer three quick questions: how many days of supply you want to keep in one case, how you will mostly use the case (travel, both, or stocking up at home), and whether you want a size guaranteed to fit any brand. The tool maps those answers to the Small, Medium, or Large capacity ranges, applies a few common-sense adjustments (for example, rounding up for stock-up routines and favoring the most compact size for travel), and recommends the best match with a direct link to buy it. Everything runs in your browser and nothing is uploaded.
Is a bigger contact lens case worth it?
It is worth it if you genuinely stage a lot of supply at once. A Large case means fewer refills and one place to see your whole quarter at a glance, which is handy at home. But bigger is not automatically better. If you mostly carry a week or two, a Large case rides around mostly empty and takes up more space than you need. The right answer is the smallest size that comfortably holds the supply you actually keep staged, and the finder is built to land you on exactly that size.