Possibly the most important, and at the same time one of the most basic methods of selection support, is to offer your customers the ability to narrow down your product range to a manageable quantity according to their own logic. Your goal is to help them reduce the number of items they are viewing to make it easier to decide which product to purchase. We’ve already looked at the optimal number of products, typically less than 50 per page, but at least 10 products.

The most important tools of narrowing down are categorization, filtering, and search. Filtering begins on the home page. This is where your customer makes their first decision, by choosing a category page, or a direct link to a product page. Your category pages handle any filtering or selection after the home page. Most sites should have a search box located in the top bar with suggested results to help customers find what they need fast. Let’s see how each type of narrowing down works.

3.2. Categorization types

A single product range can be categorized according to a number of factors. However, many online stores categorize their products following only one way of logic. By doing so, they may lose a large number of customers who could not find the product category appropriate for them.

How well you have defined your customer groups and how much you understand their way of thinking thus becomes really significant. The following questions should be asked for all your important customer groups:

• If I were part of the specific customer group, how would I select from these products?
• How can I narrow down the number of products to a manageable level?
• What questions will I have?
• Could I find the products most appropriate for me according to these categories?

Often, categorization for your customer has nothing to do with “official” categorization, as in how you purchase from wholesale. For example, in the case of books, while a book seller may purchase based on publisher, people searching for books are more likely to search based on topic so using the publisher for categorization wouldn’t be very helpful.

You’ll likely find that different customer types think differently and select differently, so you need categorization based on different logic types. This is referred to as parallel categorization. This is a process whereby you categorize your products in multiple categories based on different logic. As result, some products will appear “in parallel” across two or more categories.

While this may seem redundant, it allows customers in different customer groups to use their own way of thinking to find the same product and reach the same conclusion: your product is just right for them.

Let’s look at the most common categorization types:

Functional categorization

Functional categorization means grouping the product range according to its “function”, or use-case. Functional categorization is usually the most common categorization it is essential for determined customers. When someone knows exactly what kind of product they need, they will generally use functional categorization.

Some examples:

• Furniture: table, chair, dresser, lamp
• Flower: cut, potted, and within that by type: rose, lily
• Computer: desktop, notebook, component, accessory, software
• Clothing: pants (trousers), t-shirt, skirt, shirt

Target market or demographic categorization

This is when products are grouped according to your customers’ demographic criteria, such as type, sex, age, etc.

Some examples:

• Flower: for wife, mother, friend
• Clothing: men, women, children
• Toys: under the age of 3, 3-8 years, 9-18 years, adults

Application categorization

It may be helpful sometimes to search for products according to where and how the specific product range is used, in other words, where it is applied.

Some examples:

• Furniture: dining room, kitchen, living room, bathroom
• Flowers: birthday, wedding, funeral, anniversary
• Computer: Internet, gaming, business, travel

Solution categorization

There are typical product ranges that offer solutions to specific problems, regardless of what functional category they fall into.

Examples:

• Food supplements: weight loss, weight gain, anti-aging, cellulite
• Medical supplements: diabetes, heart problems, allergies, osteoporosis

Special or specification categorization

Almost all product ranges have specific characteristics by which they can be grouped, and then categorized. Also, there are product ranges where products are typically selected according to these parameters.

Some examples:

• Computer Monitor: categorization by screen size: 15", 17", 19", 20", >20", screen refresh rate: 16ms, 10-16ms, 4-10ms, 2-4ms, 1-2ms, connections: DVI, VGA, DisplayPort
• Flowers: categorization by stem length, quality, origin
• Clothing: categorization by material, washing instructions, color
• Any product range: categorization by price: < $50, $50–$100, $100–$250, brand: Samsung, LG, HP, Dell

The possibilities are endless, and there are as many categories as there are product ranges. This is when being knowledgeable about your products and having previous experience selling them is really important. You must know how your customers make a selection.

In a brick and mortar store, a customer can ask any questions they wanted before purchase. Selling online, you have to take it a step further, and anticipate your customers’ questions in advance. Based on your understanding, you want to make selecting your products as easy as possible without a dedicated salesperson to answer questions at the time of sale.

The existence of clear, logical categorization on your site is enough for determined customers, but the majority of solution-seeking visitors and browsing visitors can be converted to customers when we guide them with some form of logic for selecting a product online.

You can see thoughtful categorization was used in the design of BlueNile.com. Their main categorization is a hybrid of functional and application-based categorization, and a detailed information sub-page is also located in the main category menu.

3.4. Filtering

Filtering occurs when a product range already narrowed down by categorization can be further narrowed down based on another product characteristic. Most common filtering is based on price, manufacturer, or some other element of the product range, for example:  screen size, dress size, or discount products.

Unlike sorting a list, filtering uses options in a side or top menu to narrow down the number of products that are displayed. The filtering can occur independently of the sort order of the products in a list. Let’s look at some examples:

Example #1

You are browsing a site for computer processors and you choose the computer->component->processor category which yields 200 processors in the category. You filter these by brand, let’s say you are only interested in AMD. Then, let’s say you filter them by price to display only processors costing $150-$200.

Example #2

You are browsing a site for flowers for a wedding bouquet, so you select wedding bouquets. Then you filter wedding bouquets to display only those that contain roses. Then you further filter the product list to display only bouquets that cost $75-$100.

Filtering is the highest, most refined level of product selection support. It minimizes the compromise necessary on category pages and, your customers don’t have to make “either-or decisions” to navigate through categories and sub-categories.

You can have an unlimited number of filters with only their display and the existing product characteristics setting the limits. However, it’s best to keep the filters limited to between five and ten in number to keep your customers moving forward with their decision. Some technical sites may have more depending on the specifications of a product range. There are numerous solutions for adding filters to a site. Let’s take a look at a few examples:

Amazon’s filter is a good example of finding relevant filters under seemingly all conditions. Even in the case of a mixed selection - such as kitchen appliances, it recommends numerous filters: colors, additional categories, manufacturer, free shipping, novelties, discount levels, customer reviews, and, of course, price.

Also, the Dell.com product filter is one of the nicest filter examples. Filtering is extremely simple and logical, and several options can be selected based on specific conditions.

Shoes.com features a very large filter at the top of their page. The solution is not recommended best practice for most sites because the filter takes up a large amount of screen space. However, it appears to make sense for the site because they carry a large number of products with the same characteristics to be filtered.