Imagine walking into an electronics store with no departments, no signage and no clearly separated product groups; coffee makers stand next to the televisions, then come phone cases, then a washing machine and a few HDMI cables. You probably wouldn't browse for long before moving on.
In a webshop, the same thing happens even faster — the visitor doesn't have to walk out of the store. One click is enough, and they're already browsing another webshop's range.
That's why we like to say the category system is far more than a simple admin setting; it's essentially the map of your webshop, helping the customer navigate the range and get to the product they're looking for. Build it well, and the visitor barely notices it, because everything is exactly where they expect it. But if the menu system is inconsistent, overly complicated or hard to understand, they'll leave quickly without ever really looking at what you offer.
A good category system isn't built for you — it's built for your visitors
If you've been working with the same products for a long time, it's easy to take for granted the system you navigate comfortably — but your customer may search by an entirely different logic.
In a technical webshop, for example, the breakdown Network devices → WLAN → 802.11ax devices may be perfectly correct professionally, while most customers simply want to find a Wi-Fi router.
The difference isn't just a matter of wording. A good category system reflects how the customer thinks and searches. That's why, when designing your category tree, it's worth setting aside internal SKUs, supplier structures and ERP categories, and starting instead from one simple question: if you were seeing this range for the first time, where would you look for this product?
A menu isn't good because it offers lots of choices
With a larger product range, it's easy to fall into the trap of creating more and more separate categories. At first this seems logical — the more precisely we name something, the easier we assume it is to find. Beyond a certain point, though, exactly the opposite happens: too many menu items make navigation harder and needlessly complicate the purchase.
The Baymard Institute's e-commerce UX research regularly deals with this problem. In 75% of the webshops examined in the organisation's benchmark, they found categorisation errors that can make products harder to find. Take a simple example. If you sell shoes, categories like black running shoes, white running shoes, blue running shoes or red running shoes can easily emerge. At first glance these look like neatly separated groups, but in reality colour doesn't necessarily justify a category of its own — it's merely an attribute of the same product type.
A far clearer solution is for the customer to first reach the right product group via Sports shoes → Running shoes, then narrow the range there by colour, size, brand or other attributes. The menu stays simple, while the number of filtering options doesn't shrink at all.
This is one of the most important distinctions to keep in mind when designing the structure of a larger webshop: not every product attribute needs its own category. In many cases, a good filter system helps the customer more than yet another menu item.
Category or filter? A lot rides on this
The boundary between category and filter isn't always obvious at first, yet a lot depends on it when building a larger webshop. A good starting point is to ask whether the customer thinks of the group as a product type in its own right, or just wants to narrow the selection by an attribute. If someone is specifically looking for an OLED television, it may well deserve its own category — especially if search behaviour and the structure of your range support it. A "55-inch television", on the other hand, is really a size-based narrowing, since screen diagonal alone doesn't constitute a new product type.
The same goes for attributes like price, colour, brand or various technical parameters. It's generally not worth spawning ever more categories from these, because the menu quickly becomes overcrowded. It's far better for the customer to first reach the right product group, then quickly narrow the range there with a few well-chosen filters.
According to Baymard's product list research, there are five general filter types that are especially important wherever relevant: price, rating, colour, size and brand. Yet 51% of the webshops examined in their 2025 benchmark failed to provide all of them properly.
Of course, no filter system works the same way in every webshop. An auto parts webshop has entirely different priorities than a clothing or electronics store. The point isn't to offer as many filters as possible, but to provide the ones that genuinely help the customer decide during the purchase.
In short, the goal is really to get the customer — with as few clicks and as little thinking as possible — to the handful of products that matter most to them.
Think in trees, not endless menu rows
The categories of a well-built webshop usually follow a clear hierarchy. In a DIY store, the path Tools → Power tools → Drills can feel completely natural, because every step takes us to a more clearly defined product group.
The problems usually begin when this logic is carried too far. A structure like Drills → Hammer drills → 600–800 watt hammer drills → Hammer drills with 13 mm chuck shows that product attributes are slowly taking over the place of categories.
The category tree's primary job is to get the customer to the product group they actually care about. From there, it's better to work with filters — narrowing by power, chuck size or other technical parameters is much faster than navigating through yet more submenus. Mix these two roles up, and you can easily end up with a menu system that's professionally accurate yet hard to see through. The customer has to make more and more decisions while, in truth, they're still just trying to figure out where to find the right products.
Sellvio offers a suitably flexible system here: categories can be built hierarchically, multiple levels of subcategories can be created under main categories, and the order can be controlled separately. Each category can get its own image, description, plus SEO and social sharing data, so the structure can be shaped not only for navigation but for content and search optimisation too. A deep category tree is technically easy to create — but that doesn't mean you need one. A good structure isn't advanced because it has many levels; it's good because the customer can reach the right product group without having to think.
Feel free to forget the three-click rule
For a long time, common advice held that every important piece of content on a website should be at most three clicks from the homepage. It sounds good at first, but in reality it oversimplifies the issue. What bothers customers usually isn't having to click four times instead of three — it's not being sure which way to go next. In a well-built category tree, several steps can feel completely natural, as long as every decision point is clear and follows logically from the previous one.
In a clothing webshop, for example, the path Women → Shoes → Sports shoes → Running shoes means four separate choices, yet it doesn't feel complicated. With every step, the customer moves unmistakably closer to the product type they actually want. By contrast, a huge menu offering twenty or thirty options at once can easily be overwhelming — even if, technically, every product is reachable in fewer clicks.
Don't make category names the outlet for your creativity
As a marketer, it's easy to slip into giving menu items catchy, creative names too. Labels like "Home experiences", "The soul of the kitchen" or "In motion" may work fine in a campaign, a banner or an inspiration page — but in the main menu they mostly create uncertainty. The customer doesn't want to decode your menu; they want to understand, as quickly as possible, where to find what they're looking for. If you sell coffee makers, a Coffee makers category is almost always a better choice than "Perfect mornings". The same goes for Garden furniture, which is far clearer than a more atmospheric but less precise "Summer in the garden" menu item.
A good category name is often downright simple — it may even seem boring — but that's not a drawback, it's an advantage. Navigation's primary job isn't to entertain or surprise the visitor, but to show them quickly and unambiguously which way to go. Creative wording certainly has its place in a webshop — just not necessarily among the category names. In the menu, clarity is usually worth more than cleverness.
Menu structure also depends on the size of your range
A webshop with twenty products needs entirely different navigation than an online store with tens of thousands. With a smaller selection, a few well-chosen menu items can easily be enough; with a bigger catalogue, the task becomes showing many categories without the menu getting cluttered.
This is where the so-called mega menu can come to the fore. Sellvio supports several kinds of category menu display, so you can build a traditional dropdown menu, a sidebar category menu or a more complex mega menu. When choosing, though, what matters most isn't which solution looks more impressive, but which best fits the size and structure of your range.
If you have just five or six main categories, a simple dropdown menu can serve customers perfectly. But if twelve main categories hold another fifty or sixty subcategories, a well-structured mega menu can give a much faster overview — and, not incidentally, force the visitor to hunt around less. Menu design, then, isn't merely a question of aesthetics. It's as much a part of product categorisation as the category tree itself, since ultimately it determines how the customer can find their way around your range.
On mobile, every categorisation mistake looks bigger
What fits comfortably on a desktop screen can easily become cramped and hard to use on mobile. A large, multi-column mega menu may be perfectly clear on a monitor, but on a phone the same structure demands far more scrolling, tapping and deciding.
When designing a category system, we mostly look at the large-screen version — but the customer may be trying to find their way around that same range on a 6.3-inch display, where every unnecessary category level and ambiguous menu item becomes far more disruptive. In Baymard's 2025 research, 67% of the mobile webshops examined had mediocre or poor homepage and category navigation UX performance. That's especially remarkable considering these weren't a handful of outdated webshops, but leading American and European e-commerce sites.
That's exactly why a simple, easy-to-follow structure matters even more on mobile. The main product categories should be easy to reach, and subcategories should open logically beneath them — ideally without the customer having to fight their way through multiple menu layers.
Baymard also pointed out that on mobile, hiding important product categories behind a generic "Products" menu item can cause needless friction. If the visitor has to search even within the navigation for where your range actually begins, you've just placed one more obstacle in their way. On mobile, then, it's not enough for the menu to work: it has to be understandable and usable at first glance.
A filter system is only as good as the product data behind it
There's a less glamorous side of webshop building whose importance only becomes apparent once you're managing hundreds or thousands of products: the consistency of product data. Sadly, a great many webshops do a poor job here — even the market leaders.
It's no use creating a well-functioning "Colour" filter if one product says black, another says Black, a third says black/grey, and a fourth has the field empty altogether. The filtering technically exists, yet the customer doesn't get reliable results.
With a larger product catalogue, it's worth defining right at the start which attributes are mandatory in each category and which values may be used. That way you avoid the same information entering the system under different names, in different formats, or incompletely.
In Sellvio, filters can be assigned to specific product categories, and the values can be predefined. For the "Colour" field, for example, you can set Black, White, Red or Blue in advance, so the same data doesn't have to be typed in as free text with every product upload. The order of filters can also be controlled, so the customer meets first the criteria that genuinely matter for the given product range. With a few dozen products this may still look like an administrative detail — with thousands, it's what decides whether filtering will actually be usable.
You won't even notice — and missing filter data will eat your profit
One of the biggest problems with incomplete product data is that the losses it causes often go unnoticed. Suppose you have 250 laptops in your range, and the customer narrows the results to 16 GB RAM, a 512 GB SSD and a 14-inch display. The system ends up showing them 2 matching models. In reality, though, another 12 laptops would also meet these criteria — but on some the RAM size isn't filled in, on others the display data is missing. So the filter simply leaves them out of the results. From the customer's perspective, these products effectively don't exist — even though the model they'd ultimately buy might be among them.
This shows clearly why categorisation, the filter system and product data management shouldn't be treated as independent tasks. A well-designed filter is only worth anything if the data behind it is filled in consistently and properly.
Sellvio supports this with a dedicated "Missing filters" admin page. There you can check, category by category, which products are missing a required filter value, and the results can be exported too — making it easier to fix the gaps systematically even in a larger catalogue.
It's not a flashy feature in itself, and in a smaller webshop it may not even seem particularly important. But when your range grows from a few hundred products to tens of thousands, it's exactly these background tools that keep the catalogue not just bigger, but still searchable and manageable.
Don't show everything at once
A common mistake is for the webshop owner to try to display the entire range already in the main menu. The intent is understandable: if a product group is available in the store, it would be nice for the customer to see it right away. The problem is that a menu is not a catalogue index, and beyond a certain point, too many choices hinder orientation rather than help it. If eighteen main categories, seventy subcategories and more than a hundred further menu items appear at once, the advantage of a large range easily drowns in the clutter. At that point, order and grouping become more important: the most sought-after categories should come first, and related product groups should sit logically next to each other. Rarely searched or less important categories don't necessarily need the same emphasis.
In Sellvio's category system, the order of categories and subcategories can be arranged separately — and it's worth using this as a genuine business tool. There's no rule saying the menu must follow alphabetical order if customer behaviour justifies entirely different priorities.
If, say, 40% of your visitors are looking for phone cases while only 2% want a memory card reader, there's little sense in giving the two the same navigational weight. A good menu doesn't show everything equally — it highlights what genuinely matters to your customers.
The category page shouldn't be just an endless row of products
A category page isn't there merely to list the products in the given group one after another. It's as much a part of navigation as the main menu itself, so in many cases it's worth giving the customer further guidance on it.
If someone enters the Garden machinery category, for example, they may not want to sift through 487 products right away. It can feel far more natural to first decide whether they're after a lawnmower, a trimmer, a hedge trimmer, a chainsaw or a pressure washer. A well-designed category page makes that next decision easier.
According to Baymard's 2026 category page analysis, 76% of the webshops examined failed to give subcategories enough emphasis on these intermediate pages. Yet these pages are perfectly suited to breaking the full range into smaller, more digestible pieces.
In Sellvio, categories can have their own image and description, so subcategories don't have to appear as plain text links. A well-chosen image and a short explanation can go a long way towards helping the customer understand at first glance which direction to head in. A good category page, then, isn't a mere transition between two menu levels, nor simply a long product list — it's more like a well-built fork in the road that helps narrow the range faster.
For SEO, the category tree is also far more than a menu
Categorisation determines not only how the customer finds their way around your webshop, but also what structure the search engine sees and interprets. A well-built category page can function as a standalone search landing page.
Suppose you sell bicycles. If you create a separate category page for electric bikes — say, under the /electric-bikes/ URL — that page can have its own title, text content, product list and internal links. You're giving a far clearer landing page to searches aimed specifically at electric bikes.
If instead you solve the same thing purely as a filter within the "Bicycles" category, the SEO picture changes. That's why the category-or-filter question shouldn't be examined from the UX side alone: you also need to check whether standalone, meaningful search demand exists for the given product group.
If customers search for a product type under its own name, and a clearly distinguishable range sits behind it, creating a standalone category page for it is often justified. If, on the other hand, it's really an attribute — colour, size or power, say — then filtering usually remains the cleaner, more manageable solution.
Sellvio's category pages have their own SEO settings, and in a multilingual webshop the categories' names, descriptions and appearance can be controlled per language. This matters especially if you sell the same range in several countries, since the same product isn't necessarily searched for with the same terms, and search habits can differ too. A good category tree thus serves the customer and the search engine at once: it helps people navigate the range while creating clear, standalone landing pages for the important search intents.
Your webshop's search won't save a bad menu system
It's easy to assume that if your webshop's search works well, a more complicated category system isn't a serious problem either. Whoever knows what they want will simply type the product name into the search box.
A large share of customers, however, don't arrive with such a specific idea. Maybe all they know is that they'd like to shade the terrace somehow — but they haven't yet decided whether they need an awning, a pergola or some other solution. They're not going to type "3 × 4 metre cassette awning" straight away; they'll look around first, open categories, compare and gradually narrow down the options.
That's why search and navigation aren't interchangeable functions. They help the customer in different situations, and in a well-built webshop they complement each other. Baymard's usability research on e-commerce search identified more than 700 search-related usability problems in the leading webshops examined — clear evidence that a search box alone doesn't solve the problem of product findability.
A good webshop offers several routes to the same product. One visitor starts from the main menu, another searches straight away, a third picks a category first and then narrows with filters. There will also be customers arriving from Google directly on a category or product page. The point is that wherever they enter your webshop, it should always be clear how to move forward. Good navigation doesn't work instead of search — it works together with it.
A good menu system is one you barely notice
That may be the best measure of whether a webshop's navigation truly works. When you enter a well-thought-out webshop, you don't think about what a splendid information architecture it has — you simply find what you're looking for. The problem usually only becomes conspicuous when you don't.
According to Baymard's research, navigation errors are common even among leading webshops. In the 2025 benchmark, 58% of desktop sites and 67% of mobile webshops achieved only mediocre or poor results in homepage and category navigation usability. In other words, even the biggest players don't get everything right in this area. Yet the underlying principle isn't complicated at all: the category should lead, the filter should narrow, the search should assist, and the menu shouldn't burden the customer with more decisions — it should make finding their way simpler.
We built Sellvio's system to provide every important tool for this on the technical side: hierarchical categories, multiple menu structures, filters manageable per category, predefinable filter values, checks for missing product data, and separate content and SEO settings for category pages. But the system only provides the framework. A good structure still has to be tailored to your range and to how your customers think. Get that right, and most customers will probably never compliment your category tree — but they'll find the right product and move on towards the purchase.