10 Ways to Optimize eCommerce Search Filters
eCommerce filters help customers find products faster and improve the shopping experience. Well-designed filters make browsing easier and increase sales. Testing and personalization keep eCommerce filters effective and user-friendly.


Updated July 16, 2025.

eCommerce product filters are a navigation tool crucial to any eCommerce platform, helping customers find products fast. Studies show that 61% of online visitors leave a website if they don’t find what they want within five seconds. With so little patience, it’s essential to make product discovery quick and easy.
Filters empower shoppers to narrow down a wide range of products effortlessly, guiding them to exactly what they’re looking for, whether they’re browsing casually or shopping with high intent.
» Add product filters seamlessly with our customized search solutions
The Use of eCommerce Filters
Effective eCommerce filter navigation reduces user decision fatigue (the mental exhaustion from too many choices) by narrowing down the often overwhelming product selection on online stores. Applying filters to highlight relevant attributes narrows down the options and reduces friction on the path to purchase.
Common Filter Suggestions Include:
- Brand
- Price
- Color
- User rating
- Material
- Size
- Theme
- Popularity
Filters can also be thematic, depending on seasons or promotions. For each different product category and collection, relevant filters should be suggested. These filters can be based on product descriptions or sourced from Google Analytics to relate to what customers are most commonly searching for.
» Struggling with search? Here's our guide to the Shopify search bar
Best Practices to Optimize eCommerce Filters
1. Horizontal or Vertical?
Vertical: Filters are most commonly found on the left-hand side of the page as a horizontal toolbar. The vertical option has the advantage of being a familiar user experience; it’s where customers expect to find them. There is the option to add a large number of filter options, as it offers the opportunity for space.
A horizontal toolbar is more visible, as it attracts shoppers' attention and adds user convenience. However, this option has limited space, and care should be taken that menus don’t automatically disappear when the cursor isn’t hovering over them.
Take Note: There is, of course, the option to employ a hybrid vertical and horizontal model. Many websites use a combination of both. The crucial thing is ensuring a seamless user experience.
» Learn about the best tools and strategies in our guide to eCommerce product search engines
2. Use A Broad Range
A ‘one size fits all’ approach does not work with filters. Some customers may be buying with intent, or some are just opening it to browse. In order to help all cases, a range of filters should be used, either product-specific or thematic.
For example, when dealing with car parts, specific terms could be used as filters to identify the models. But when selling gifts, themes such as ‘anniversary’, ‘birthday’, and ‘graduation’ could be used, which are much broader terms.
These enhance value and promote storytelling, whereas the functional filters can be employed for more high-intent buyers.
» Be sure not to make these eCommerce search mistakes
3. Keep Language Simple
Your filters should be written in the same language your customers use to search for products. Using the terms that shoppers use makes it easier for them to find what they are looking for. Rather than trying to be creative or show specialist expertise when designing the language for the filters, merchants should be thinking about what creates the least confusing customer journey.
For the same reason, avoid using industry jargon as many customers will not be experts in the product range. Remember that filters are not a branding exercise; their functionality and simplicity is far more important.
» Read more: What is natural language search?
4. Optimize for Mobile
Mobile phones continue to account for more of the eCommerce market, meaning that mobile-commerce should remain at the forefront of merchants’ minds. Having a mobile-first mentality should apply to all areas of your website, including eCommerce filters.
Filters should be optimized for mobile phone use. Ensure that the options don’t cover all of the screen, and that the filters still remain as accessible and practical on the mobile device as they do on a bigger screen.
» Make sure you know how to add search to your mobile app
5. Multiple Values Allowed
Sometimes shoppers will want to apply more than one filter, and they should always be allowed. Customers may want to select several options at a time, either if they know precisely what they are looking for, or they are unsure and want to narrow down the possible options.
Allowing customers to apply multiple filters is beneficial because it helps them find all relevant products that meet their needs, which can increase average order value (AOV – the average amount spent per order) and boost sales.
» Do you want more tips to increase your AOV? Here are 6 data-backed strategies
6. Keep It Clear
Filters are there to make the buying journey easier, so make sure this stays the case. The moment filters start to become confusing or distracting, they are defeating their purpose. It should be clear to the user when filters have been applied, so they know which filtered products they are viewing. Interactive filtering is also useful, meaning that as soon as a filter is selected the page changes.
Without the user having to take an extra step to see their preferred selection, the journey to buying is smoother. Batch filtering would only be preferable if your site has issues with speed.
» Check out our step-by-step guide to add product filters to your Shopify eCommerce store
7. Don’t Forget To Merchandise
It’s important not to overlook merchandising strategy and rules when it comes to filters. Setting promoted filters will help shoppers narrow down results and aid the merchant’s business goals. By placing certain filters at the top of the list, attention will be grabbed, and shoppers will be directed according to strategic characteristics.
This is where advanced platforms like Fast Simon's Merchandising AI Assistant become invaluable, allowing merchants to easily implement and test these strategic filter placements.
For the same reason, irrelevant filters should be buried low at the bottom of the options. This means they will only be ticked if customers actively search for them. This helps influence which sales your business makes.
Promoting filters should also be considered in terms of user ease. For example, if someone is looking for shoes, jewelry filters should be buried as they are not relevant and will not aid the current considered purchase. Ordering filters alphabetically isn’t the best strategy either; ordering them according to the customer’s frequent searches is a better strategy.
» Need more help with merchandising? Learn how to optimize your site's navigation for better merchandising
8. Personalization Still Applies
Saving and suggesting filters based on real-time shopper behavior can significantly improve the customer experience and boost conversions. Returning customers can have their eCommerce product filters preferences saved for their next visit, showing that your business values their time and choices. Using browsing history to suggest relevant filters helps shoppers find what they want faster.
Did you know? Fast Simon's personalization engine can automate the saving and suggestion of filters based on real-time shopper behavior.
» Learn more: Why use personalization in site search?
9. Consider The Numbers
When deciding how many filter options to display, the Goldilocks principle should be applied. Don’t overwhelm the shopper with too many filters, but don’t disrupt their decision process with too few. Rather than listing every color possible, for example, just display the most valuable ones. If there are more filters that you think are helpful, you can add a ‘View More’ option for customers looking to search deeper.
It’s also a good idea to display the product quantity next to the eCommerce filters. This avoids over-filtering, and people can then know whether or not it’s helpful to click on that filter or not. If there are very few products in that category, they might want to select more than one.
10. Never Show 0 Results
A golden rule in eCommerce is never to display the dreaded ‘0 Results’ page. A basic UX non-negotiable is to relocate a page with no results to related products, or relevant items based on the user behavior. Any filters that would lead to 0 results or to out-of-stock items should be buried, as this only infringes the user experience.
Fast Simon's product finder ensures that only in-stock or relevant products are ever displayed, eliminating frustration for your customers. Dynamic filtering can mean that only products that are in stock are shown, and these can be very useful.
» Product filters not enough? See these other ways to optimize internal site search
Real-World Examples of Successful eCommerce Search Filters
1. Spiceology
Spiceology, a premium spice and herb retailer, improved its eCommerce filter navigation with automatically generated vertical filters on the left. These filters makes it easy for both chefs and home cooks to find products quickly.
2. Francesca's
Francesca’s, a leading women’s fashion and lifestyle retailer, enhanced its eCommerce filter navigation using Fast Simon’s advanced search and filter solutions. Shoppers can now easily sort products by color, style, size, and price, creating a more intuitive and shopper-friendly experience.
3. Ally Fashion
Ally Fashion, a leading Australian women’s fashion retailer, optimized its eCommerce filter navigation with Fast Simon’s advanced filtering system. This allows shoppers to apply multiple filters across a large catalog and collections. The vertical filter setup, combined with optimized site search, improved product findability and created a smooth shopping experience.
» Improve filters even more with Shopify search collections
Effective eCommerce Filters: Keep Testing for Lasting Success
In order to make sure your eCommerce filters remain effective, keep on testing. Running A/B tests on filters should not be overlooked. If certain categories aren’t getting clicked, examine why. With regular testing, filters are an amazing and certain way to improve the user experience and boost conversions.
Continually optimizing your eCommerce filters helps you stay aligned with customer needs and market trends. This ongoing effort ensures your store remains competitive and keeps shoppers coming back.
» Book a demo to start leveraging the power of AI eCommerce site search tools
FAQs: eCommerce Search Filters
What are eCommerce filters?
eCommerce filters are navigational tools that let shoppers refine product listings using attributes like size, color, price, availability, and style.
How many filter options should I include?
Strike a balance—include enough meaningful options without overwhelming users. Use the Goldilocks principle: not too many, not too few.
Where should I place filters on my site?
Vertical filter panels (usually on the left) offer familiarity and space for many options. Horizontal toolbars are more visible but have limited space. You can also use a hybrid model, depending on your layout and user experience goals.