Help customers easily find their true size with detailed size charts and reduce return rate. Size Guides & Size Chart app help your customers to say goodbye to sizing frustrations. Create custom size charts with ease using size selector and AI generator. Designed for shop owners, our app lets you build accurate, true-to-size charts, size finders, size recommendation and fit guides to enhance your customers' shopping experience. Perfect for clothes size chart, shoes size or accessories. Increase your confidence, increase your profits and make sure that size matters! Size Guides & Size Chart app help your customers to say goodbye to sizing frustrations. Create custom size charts with ease using size selector and AI generator. Designed for shop owners, our app lets you build accurate, true-to-size charts, size finders, size recommendation and fit guides to enhance your customers' shopping experience. Perfect for clothes size chart, shoes size or accessories. Increase your confidence, increase your profits and make sure that size matters! more Easily create sized size charts comparison table tailored to your products. Visually showcase true size options in size table for your customers. Add detailed measurement guides to assist customers in finding the right size. Simple, intuitive sizing chart design makes it easy to find the information. Size matters & fit guide widget that works seamlessly on all devices.
Custom CSS Shopify Apps
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Boost Sales and Ignite Urgency with FOMO Sale Countdown Timer Bar to Increase Conversions! Sales count down timer bar effectively instills a sense of urgency and scarcity in your store. Elevate your customers' FOMO by adding a hurrify countdown timer, pushing them to buy. Create urgency with essential countdown banner or coundown timer, and encourage customers to make a purchase. Maximize your sales during special promotions, flash sales, and seasonal events. Transform your product launches with sales popup countdown time bar or discount timer that build hype and drive early sales. Sales count down timer bar effectively instills a sense of urgency and scarcity in your store. Elevate your customers' FOMO by adding a hurrify countdown timer, pushing them to buy. Create urgency with essential countdown banner or coundown timer, and encourage customers to make a purchase. Maximize your sales during special promotions, flash sales, and seasonal events. Transform your product launches with sales popup countdown time bar or discount timer that build hype and drive early sales. more Countdown timer ultimate tool to highlight limited-time offers with timer cart. Add customizable countdown bars, sales timer to ignite urgency and boost sales. Easily create and customize countdown cart timer to match your brand's style. Set specific triggers & rules when to show the urgency bear without any coding. Track the performance of Halloween sale timers & FOMO countdown timer.
Approve wholesale B2B buyers faster with custom wholesale forms that unlock special pricing. Wholesale Forms is a complete solution for managing B2B and wholesale processes and wholesale inquiry. Build custom multi-step registration forms to collect resale certificates, VAT IDs, or business licenses. Let resellers select preferences like packaging or shipping in the form. Simplify wholesale workflows and create a tailored experience for wholesale customers. Launch your wholesale signup form without coding in under 5 minutes and approve your first B2B customer today! Wholesale Forms is a complete solution for managing B2B and wholesale processes and wholesale inquiry. Build custom multi-step registration forms to collect resale certificates, VAT IDs, or business licenses. Let resellers select preferences like packaging or shipping in the form. Simplify wholesale workflows and create a tailored experience for wholesale customers. Launch your wholesale signup form without coding in under 5 minutes and approve your first B2B customer today! more Build advanced B2B wholesale multi step forms with a drag-and-drop form builder. Embed forms anywhere on your store or trigger them via popup. Ideal for reseller signups, vendor applications, or wholesale club access. Collect VAT IDs, resale certificates, and business licenses to stay compliant. Segment B2B customers based on form responses and approve before granting access
Effortlessly build custom RSVP forms in minutes and track responses with RSVP Form Builder. RSVP Form Builder is the easiest way to create custom event registration and RSVP forms. Perfect for weddings, conferences, parties, or private sales, it helps you track event sign ups in real time, manage multiple events, and keep everything organized. Customize every field with a simple drag-and-drop editor, match your brand style, and share your form anywhere. Simplify event planning and boost attendance - install today and make event management effortless. RSVP Form Builder is the easiest way to create custom event registration and RSVP forms. Perfect for weddings, conferences, parties, or private sales, it helps you track event sign ups in real time, manage multiple events, and keep everything organized. Customize every field with a simple drag-and-drop editor, match your brand style, and share your form anywhere. Simplify event planning and boost attendance - install today and make event management effortless. more Build custom event registration forms in minutes - no coding needed. Track sign-ups live and manage multiple events effortlessly. Export guest lists to CSV or Excel for easy organization. Fully customize fields, styles, and branding with drag & drop. Add forms anywhere and get real-time response updates instantly.
Increase your average order value with offering bundles, gifts, and applying volume discounts! Create bundles which not only boost your AOV but also increase your conversion rate. Customise it easily to match your brand with our simple bundle builder. Curious to see how it performs? Track additional revenue generated in the main dashboard or dig in deeper in our analytics. Maximise your performance with our built-in A/B testing. Do you have any questions? Chat with our live customer support. Create bundles which not only boost your AOV but also increase your conversion rate. Customise it easily to match your brand with our simple bundle builder. Curious to see how it performs? Track additional revenue generated in the main dashboard or dig in deeper in our analytics. Maximise your performance with our built-in A/B testing. Do you have any questions? Chat with our live customer support. more Select which products or collections are eligible for volume discount. Discount can be set in percentage, dollar discount or specific price. Adjust the colours and styling to match your store's look & feel. See how much additional revenue you generated in the app's dashboard. Shopify native user friendly experience & helpful live customer support.
Boost AOV with a custom slide cart featuring cart discount, urgency timer, free shipping bar, etc. Kaching Cart Drawer Upsell helps you increase AOV with a customizable slide cart. Add urgency timer, free shipping/gift bars, and payment icons to drive conversions. Upsell products through sliders or toggles like gift wrapping and shipping protection. Built with a focus on UX, Kaching makes it easy to create, customize your cart drawer and translate it to any language, no coding required. Turn every cart into a revenue opportunity with this intuitive app designed to boost sales effortlessly. Kaching Cart Drawer Upsell helps you increase AOV with a customizable slide cart. Add urgency timer, free shipping/gift bars, and payment icons to drive conversions. Upsell products through sliders or toggles like gift wrapping and shipping protection. Built with a focus on UX, Kaching makes it easy to create, customize your cart drawer and translate it to any language, no coding required. Turn every cart into a revenue opportunity with this intuitive app designed to boost sales effortlessly. more Boost AOV with upsell slider featuring frequently bought together products. Upsell gift wrap or shipping protection with simple toggle. Add urgency with countdown timers to drive faster checkouts. Display free shipping / free gift bar to encourage higher cart values. Enhance trust with payment icons in the slide cart.
Maximise your revenue with customisable upsell and cross-sell popups in your product pages. Kaching Upsell Popup shows the right add-on when a shopper adds a product to cart. Pick a trigger (add to cart, start checkout, exit intent, timer or scroll) and choose where the popup shows by page, market and audience. On install, the app scans your catalog and suggests matching add-ons for your products. Offer single products, product sliders, free gifts, or deals from Kaching Bundles and Kaching Subscriptions. Edit every popup in a no-code editor, run A/B tests, and track added revenue. Kaching Upsell Popup shows the right add-on when a shopper adds a product to cart. Pick a trigger (add to cart, start checkout, exit intent, timer or scroll) and choose where the popup shows by page, market and audience. On install, the app scans your catalog and suggests matching add-ons for your products. Offer single products, product sliders, free gifts, or deals from Kaching Bundles and Kaching Subscriptions. Edit every popup in a no-code editor, run A/B tests, and track added revenue. more Create a seamless popup experience without interrupting the buying journey Get add-on suggestions matched to the products in your catalog Boost sales offering frequently bought together products in your popups Run A/B tests and track views, add to carts, purchases and added revenue
Boost conversions and AOV with Kainic, an AI-driven personalization and analytics engine. Kainic continuously tracks real-time shopper behavior, browsing history, and buying patterns to deliver hyper-relevant product recommendations right when your customers are ready to buy. Whether it’s cross-selling on product pages, suggesting smart add-ons in cart drawers, or optimizing checkout offers, Kainic helps turn single-item visits into larger carts. Kainic continuously tracks real-time shopper behavior, browsing history, and buying patterns to deliver hyper-relevant product recommendations right when your customers are ready to buy. Whether it’s cross-selling on product pages, suggesting smart add-ons in cart drawers, or optimizing checkout offers, Kainic helps turn single-item visits into larger carts. more AI product recommendations: personalized bundles based on shopper behavior. Granular tracking: customizable events capture live interactions and intent. Flexible upsells: CSS/HTML-styled offers in cart, checkout, and product pages. Real-time dashboard: track conversion lifts and revenue attribution. Fast, no-code setup: sub-50ms inference with full branding control.
Multi location stock display, geosearch, store selector, location filters, B2B & click & collect A must-have for Shopify merchants with multiple locations: physical stores, warehouses, and click & collect points. Show stock levels and incoming inventory per location on product pages. Let customers geosearch a store locator to find nearby available stock. Build smart collections and filters by location availability. Restrict ordering by customer tags for B2B wholesale & company accounts. Sync inventory into metafields for custom workflows & ERP integrations; Back-in-Stock alerts per location A must-have for Shopify merchants with multiple locations: physical stores, warehouses, and click & collect points. Show stock levels and incoming inventory per location on product pages. Let customers geosearch a store locator to find nearby available stock. Build smart collections and filters by location availability. Restrict ordering by customer tags for B2B wholesale & company accounts. Sync inventory into metafields for custom workflows & ERP integrations; Back-in-Stock alerts per location more Display stock levels & incoming inventory per location on product pages Build smart collections & filter by location stock availability via metafields Access location inventory JSON metafields in Liquid for custom workflows & ERPs Store selector for click and collect, local pickup & location-based purchasing Assign warehouse locations to B2B companies for controlled inventory ordering
Customizable in-store search with great UX, realtime updates, automatic filters and AI Kea Labs Smart Search replaces in-store Search by two parts: rapidly fast search widget with suggestions and Search Results page with automatic filters. We focus on solving business needs and provide a unique combination of SaaS with a professional solution team. If you are tired of limitations of ready SaaS services, manual case-by-case adjustments, and inability to solve your business requirements, Kea Labs is the solution for you. A free consultation with integration specialists available. Kea Labs Smart Search replaces in-store Search by two parts: rapidly fast search widget with suggestions and Search Results page with automatic filters. We focus on solving business needs and provide a unique combination of SaaS with a professional solution team. If you are tired of limitations of ready SaaS services, manual case-by-case adjustments, and inability to solve your business requirements, Kea Labs is the solution for you. A free consultation with integration specialists available. more Self-learning AI Search. Continuously improves relevance. Suggestions, filters and autocomplete. No typing experience on mobile. Advanced linguistics: spell-tolerance, context, synonyms, multilingual search. Automatic synonyms detection. Forget about doing this manually. Evaluates potential profit, demand trends and customer interests.
Displays live precious metal prices, ideal for selling fine jewelry, bullions and coins. Keep Up With Metals helps you display real-time precious metal prices directly on your storefront, giving your customers up-to-date information on gold, silver, platinum, and more. Customize the widget to match your store’s style, apply flexible markups, and easily adjust settings. Perfect for stores selling jewelry, bullion, or any metal-based products, this app ensures pricing transparency and improves customer trust, helping drive sales and engagement with minimal setup required. Keep Up With Metals helps you display real-time precious metal prices directly on your storefront, giving your customers up-to-date information on gold, silver, platinum, and more. Customize the widget to match your store’s style, apply flexible markups, and easily adjust settings. Perfect for stores selling jewelry, bullion, or any metal-based products, this app ensures pricing transparency and improves customer trust, helping drive sales and engagement with minimal setup required. more Real-time metal prices for gold, silver, platinum, palladium and more Customizable widget design to match your store’s theme. Flexible markup options: percentage or fixed amount adjustments. Track impressions, clicks, and revenue with built-in analytics dashboard. Seamless integration with Shopify for easy setup and use.
Turn searches into sales - Find, Select, and Buy – Directly from Your Search! Lost sales are often the result of frustrating search experiences, where customers leave without finding what they need. Kesem AI transforms your search bar into a conversion engine—offering instant, personalized visual product matches, variant selection, and direct cart addition, all within the search view. It’s a seamless path from search to checkout, eliminating barriers and boosting sales effortlessly. Kesem AI turns your search bar browsing into buying! Lost sales are often the result of frustrating search experiences, where customers leave without finding what they need. Kesem AI transforms your search bar into a conversion engine—offering instant, personalized visual product matches, variant selection, and direct cart addition, all within the search view. It’s a seamless path from search to checkout, eliminating barriers and boosting sales effortlessly. Kesem AI turns your search bar browsing into buying! more Instant Recommendations: Personalized product suggestions directly in search. Real-Time Variant Selection: Choose colors, sizes, and options within the search One-Click Add-to-Cart: Add products to cart directly from search. Conversational Search Intelligence: Understands intent, offering relevant result Seamless Modal-to-Chatbot Transition.
Build Your Own Ring Using Diamonds, Intelligent Filters & AI Launch a complete custom ring design experience that lets shoppers start with a diamond or setting and create their perfect ring in three simple steps. Showcase 500K+ loose diamonds, including natural, lab-grown, colored diamonds, sapphires, emeralds and rubies. Import inventory via feeds or CSV and connect Nivoda, RapNet, VDB, KIRA, Belgium Diamonds, Stuller and Overnight Mountings. Support GIA and IGI certified stones, US, AU and EU currencies, ring sizes and customizable profit margins. Launch a complete custom ring design experience that lets shoppers start with a diamond or setting and create their perfect ring in three simple steps. Showcase 500K+ loose diamonds, including natural, lab-grown, colored diamonds, sapphires, emeralds and rubies. Import inventory via feeds or CSV and connect Nivoda, RapNet, VDB, KIRA, Belgium Diamonds, Stuller and Overnight Mountings. Support GIA and IGI certified stones, US, AU and EU currencies, ring sizes and customizable profit margins. more Use your collections to build rings, pendants, earrings with 2 diamond options Ask AI to help customers find the right diamond faster Apply markups, strikethrough discounts, and track sales, revenue and profit Add engraving, hide certificate numbers, and unlock premium add-ons Optimize shopping with mobile grid view and advanced customization
Create unlimited app options to help merchants increase sales. This app helps you to create infinite product options, which help merchants sell their products and increases sales. Allow shoppers to design their own custom products based on flexible option choices. The function of "option template" can manage options more flexibly. This app is compatible with drawer cart and buy now button. This app helps you to create infinite product options, which help merchants sell their products and increases sales. Allow shoppers to design their own custom products based on flexible option choices. The function of "option template" can manage options more flexibly. This app is compatible with drawer cart and buy now button. more Create unlimited app options to help merchants increase sales. Support ajax cart and "buy it now" Compatible with Online Store 2.0 Themes Flexible and unlimited options template
Hide / Rename / Reorder payment methods the way you want, based on the conditions that you set. Customize the checkout experience of your customer to your needs! You can rename, reorder and hide payment methods that you set based on conditions like customer country/location, selected shipping method, cart total, cart weight, specific items SKUs, digital products, customer tags, customer is a company and more. Also, you can hide express checkout. Give priority to payment methods by moving them to the top so they are preferred by your customers, or block the checkout by hiding all methods. Customize the checkout experience of your customer to your needs! You can rename, reorder and hide payment methods that you set based on conditions like customer country/location, selected shipping method, cart total, cart weight, specific items SKUs, digital products, customer tags, customer is a company and more. Also, you can hide express checkout. Give priority to payment methods by moving them to the top so they are preferred by your customers, or block the checkout by hiding all methods. more Reorder, hide, or change the name of payment methods on the checkout page Unlimited rules to hide/rename/sort payment methods Rename payment options by country / language or any other condition that you set Hide the express checkout at the product page, cart page and checkout page Hide Cash on Delivery (COD) in countries / locations that you set
Reduce holiday & gift returns, increase sales with AI-powered size charts, guides & recommender When customers aren't sure about sizing, they hesitate, or return their order, which gets costly during the holidays. Kiwi helps you remove that uncertainty with customizable size charts and AI-powered fit recommendations that guide shoppers to the right choice. The result? More confident purchases and fewer returns. Add size charts and smart recommendations to any product, from apparel to more. No code, quick setup. Launch in minutes and create a sizing experience that matches your brand. When customers aren't sure about sizing, they hesitate, or return their order, which gets costly during the holidays. Kiwi helps you remove that uncertainty with customizable size charts and AI-powered fit recommendations that guide shoppers to the right choice. The result? More confident purchases and fewer returns. Add size charts and smart recommendations to any product, from apparel to more. No code, quick setup. Launch in minutes and create a sizing experience that matches your brand. more Import unlimited size charts from images, product descriptions, or CSV Help customers find their perfect fit with AI-powered size recommendations Add multiple size tables, images, videos, tabs, and more to your size charts Create a product or collection-based size guides that auto-apply to new products Automatically update the sizing unit based on your customer's location
AI Search & product discovery platform that significantly improves conversion rate and AOV. Perfect for busy merchandising teams, Klevu advanced AI search and recommendations engine helps companies efficiently increase on-site search revenue. Plus, shoppers get personalized product recommendations, and are able to quickly find what they need through our filter and navigation features on product listing pages. Fully compatible with Shopify Markets. With our innovative features, retailers can provide customers with an enjoyable, streamlined shopping experience. Perfect for busy merchandising teams, Klevu advanced AI search and recommendations engine helps companies efficiently increase on-site search revenue. Plus, shoppers get personalized product recommendations, and are able to quickly find what they need through our filter and navigation features on product listing pages. Fully compatible with Shopify Markets. With our innovative features, retailers can provide customers with an enjoyable, streamlined shopping experience. more Advanced AI search and merchandising that learns from your shoppers over time. Easy-to-use merchandising dashboard where you can test and schedule campaigns. Add advanced filtering to product listing pages and manage facets shown. Onsite Search, Merch & Recommendations fully compatible with Shopify Markets. Robust APIs, SDKs and custom storefront documentation, compatible with Hydrogen.
Provide instant answers to customer questions and improve user experience. Transform your store with modern, user-friendly FAQ pages that cater to all your customers' needs. Create product FAQs effortlessly and even showcase them on your shop's app. With our app, you have full control over customization, from adjusting fonts, and colors, to styles, ensuring your FAQ page aligns perfectly with your brand. Experience lightning loading times for your FAQs, guaranteeing that your customers get answers in the blink of an eye. Transform your store with modern, user-friendly FAQ pages that cater to all your customers' needs. Create product FAQs effortlessly and even showcase them on your shop's app. With our app, you have full control over customization, from adjusting fonts, and colors, to styles, ensuring your FAQ page aligns perfectly with your brand. Experience lightning loading times for your FAQs, guaranteeing that your customers get answers in the blink of an eye. more Display FAQs on the home page or custom pages for maximum impact. Match your FAQs to your store's design and brand identity. Automatically generate and update FAQs for timely, relevant information. Improve search engine visibility with optimized FAQ content.
Add visual menus and product quizzes to guide shoppers to products, collections, and links Add a circle menu bar to your theme section & anywhere in your Shopify 2.0 theme. Create a social media familiar menu to feature products, collections, pages, & links with clean thumbnail navigation. Build collection menus like Instagram stories so shoppers can quickly navigate from collections to specific items. You can also create product quizzes that ask shoppers questions & send them to the right product, collection, or recommendation, helping reduce bounce rate & improve conversion. Add a circle menu bar to your theme section & anywhere in your Shopify 2.0 theme. Create a social media familiar menu to feature products, collections, pages, & links with clean thumbnail navigation. Build collection menus like Instagram stories so shoppers can quickly navigate from collections to specific items. You can also create product quizzes that ask shoppers questions & send them to the right product, collection, or recommendation, helping reduce bounce rate & improve conversion. more Create image-rich menus for collections, products, and any link Show different menu groups by page, collection, product, or campaign Build product quizzes that guide shoppers to the right products Customize circle menu, badges, borders, spacing, layouts, and mobile display Translate menu labels for different storefront languages and markets
Cart Drawer to Boost AOV: Upsells, Cross-Sell, Rewards, Free Gift & Fast Checkout Kraken Cart helps online stores increase revenue with a fully customizable cart drawer. Display relevant product recommendations with cross-sells, add upsells, and offer tiered rewards such as discounts, free shipping, or free gifts. Enable features including shipping protection, subscriptions, discount codes, gift wrap, order notes, and trust badges. Designed to match your brand and deliver a seamless shopping experience across desktop and mobile devices. Easy setup with no coding required. Kraken Cart helps online stores increase revenue with a fully customizable cart drawer. Display relevant product recommendations with cross-sells, add upsells, and offer tiered rewards such as discounts, free shipping, or free gifts. Enable features including shipping protection, subscriptions, discount codes, gift wrap, order notes, and trust badges. Designed to match your brand and deliver a seamless shopping experience across desktop and mobile devices. Easy setup with no coding required. more Motivate shoppers with in-cart rewards unlocking discounts or gifts. Increase sales with upsells and cross-sells directly in the cart drawer. Offer shipping protection options right within the cart for peace of mind. Enable customers to select subscription plans directly from the cart. Build trust by displaying custom badges directly in the cart interface.
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About Custom CSS Apps for Shopify
Custom CSS apps are essential tools for Shopify merchants looking to enhance their store's functionality and improve customer experience. These specialized applications help store owners streamline operations, increase sales, and provide better service to their customers.
When choosing a custom css app for your Shopify store, consider factors such as features, pricing, customer support, and compatibility with your theme and other apps. Reading reviews from other merchants can also provide valuable insights into the app's performance and reliability.
The apps listed on this page represent some of the best custom css solutions available in the Shopify App Store. Each has been selected based on its functionality, user ratings, and overall value for Shopify merchants.