TL;DR
Both Caddy and Fast Cart are free WooCommerce side cart plugins, but they serve very different needs. Fast Cart is an ultra-lightweight, no-frills AJAX cart at just 16 KB. Caddy’s free version includes product recommendations, a free shipping meter, save for later, coupons in cart, and more, plus a Pro upgrade path with analytics, automation, and abandoned cart tracking for stores ready to scale.
Best for:
- Caddy: Store owners who want a feature-rich cart experience out of the box and the option to unlock revenue optimization tools as they grow.
- Fast Cart: Developers or store owners who need the absolute smallest footprint possible and only require basic add-to-cart functionality.
Overview
Side cart plugins have become essential for WooCommerce stores. A well-designed slide-out cart reduces friction, keeps shoppers on the page, and creates opportunities to increase average order value before checkout. The question is how much your cart should actually do.
Caddy is a smart side cart plugin built by Tribe Interactive with over 4,000 active installs on WordPress.org. Version 3.0.0 is built on the WordPress Interactivity API and WooCommerce Store API, a modern architecture that ensures long-term compatibility as WordPress evolves. The free version ships with features most competitors lock behind a paywall, and the Pro tier adds analytics, automation, and abandoned cart recovery for stores that want data-driven optimization.
Fast Cart by WPXtension is a minimalist side cart plugin with around 200 active installs. It does one thing (provide an AJAX slide-out cart) and does it in an impressively small package. At 16.2 KB of combined CSS and JavaScript, it is one of the lightest cart plugins available. There is no premium version. What you see is what you get.
Both plugins are free. Both support HPOS and block themes. But the similarity ends there.
1. Features Breakdown
This is where the gap between these two plugins becomes clear. Caddy’s free tier alone includes more functionality than Fast Cart offers in total, and Caddy Pro extends that further into analytics and automation territory.
| Feature | Caddy (Free) | Caddy (Pro) | Fast Cart |
|---|---|---|---|
| AJAX Side Cart | Yes | Yes | Yes |
| Floating Cart Icon / Bubble | Yes | Yes | Yes |
| Quantity Controls | Yes | Yes | Yes |
| Remove Items from Cart | Yes | Yes | Yes |
| Free Shipping Progress Meter | Yes | Yes | No |
| In-Cart Product Recommendations | Yes | Yes | No |
| Save for Later | Yes | Yes | No |
| Rewards Meter | Yes | Yes | No |
| Apply Coupons in Cart | Yes | Yes | No |
| Announcement Bar | Yes | Yes | No |
| Menu Cart Widget / Shortcodes | Yes | Yes | No |
| Custom CSS | Yes | Yes | No |
| Light / Dark Mode | No | No | Yes |
| Brand Color Customization | Yes | Yes | Yes |
| Multiple Button Styles | Yes | Yes | Yes (2 styles) |
| Sale Price Display | Yes | Yes | Yes |
| Analytics Dashboard | No | Yes | No |
| Revenue & Conversion Tracking | No | Yes | No |
| Abandoned Cart Tracking | No | Yes | No |
| Workflow Automation | No | Yes | No |
| Free Gifts & Offers | No | Yes | No |
| Advanced Display Rules | No | Yes | No |
| Cart Session Monitoring | No | Yes | No |
| HPOS Support | Yes | Yes | Yes |
| Block Theme Compatible | Yes | Yes | Yes |
Fast Cart covers the basics competently. You get a clean slide-out cart with quantity controls, item removal, a floating cart icon, and the ability to customize colors and toggle between light and dark modes. That is the complete feature set.
Caddy’s free version goes significantly further. The free shipping progress meter alone is a proven AOV driver, showing customers exactly how much more they need to spend for free shipping consistently lifts cart values. Add in-cart product recommendations, save for later, a rewards meter, coupon support, and an announcement bar, and you have a cart that actively works to increase revenue, not just display products.
Caddy Pro then adds the data layer. The analytics dashboard tracks which features are actually driving revenue. Abandoned cart tracking captures potential lost sales. Workflow automation lets you create rules-based experiences, like showing a free gift offer when cart value hits a threshold. These are the tools that separate a basic cart from a conversion engine.
2. UX and Design
Caddy:
Caddy is designed to look polished immediately after activation. The side cart integrates smoothly with popular themes and adjusts to match your store’s design language. The visual customizer lets you modify colors, positioning, and styling without writing code. Mobile responsiveness is built in. The cart adapts to every screen size without additional configuration.
The UX is intentionally layered. Customers see the core cart experience first, then discover helpful touches like the free shipping meter filling up as they add items, or relevant product recommendations that feel natural rather than pushy. The save for later feature keeps wishlist items visible without cluttering the active cart. Everything is designed to reduce friction and increase the chance a customer completes checkout with a higher cart value.
Fast Cart:
Fast Cart prioritizes simplicity in its design approach. The light and dark mode toggle is a nice touch that most side cart plugins do not offer natively. The interface is clean and uncluttered, which makes sense given the limited feature set. There are no meters, recommendations, or extra UI elements to manage.
Customization is limited to color adjustments, button style selection, and the light/dark toggle. If your store has a specific visual identity and you need the cart to match precisely, you will have fewer knobs to turn with Fast Cart compared to Caddy.
Bottom Line: Caddy delivers a more complete and conversion-optimized user experience. Fast Cart offers a clean, minimal interface that stays out of the way. If you want your cart to be invisible, Fast Cart works. If you want your cart to work for you, Caddy is the better choice.
3. Performance and Speed
Performance matters. A side cart plugin that slows down your store defeats its own purpose.
Fast Cart:
This is where Fast Cart genuinely stands out. At 16.2 KB of combined CSS and JavaScript, it is remarkably lightweight. For stores where every kilobyte counts, particularly those already dealing with heavy themes, large product catalogs, or aggressive performance budgets, Fast Cart adds almost zero overhead. Credit where it is due: this is an impressive engineering achievement.
Caddy:
Caddy 3.0.0 is built on the WordPress Interactivity API and WooCommerce Store API. This modern architecture means Caddy uses the same APIs that WooCommerce core relies on, resulting in efficient data handling and fewer redundant requests. The JavaScript is loaded conditionally and the AJAX implementation is optimized for speed.
Caddy is heavier than Fast Cart (it has to be, given the additional features), but it is well-optimized relative to what it delivers. The analytics tracking in Pro is designed to collect data without impacting front-end performance. Regular performance audits are part of the development process.
Bottom Line: Fast Cart wins on raw file size. Caddy is heavier but well-optimized for the features it provides. For the vast majority of WooCommerce stores, the performance difference between the two will not be perceptible to customers. If your store is already struggling with performance issues, those problems almost certainly originate from your theme, hosting, or other plugins, not from the difference between a 16 KB cart plugin and a slightly larger one.
4. Pricing Comparison
This is straightforward because Fast Cart has no paid tier at all.
Caddy Pricing:
- Free (WordPress.org): Full-featured side cart with free shipping meter, product recommendations, save for later, rewards meter, coupons, announcement bar, and more
- Starter: $99/year (1 site): All Pro features
- Pro: $199/year (5 sites): All Pro features
- Unlimited: $399/year (unlimited sites): All Pro features
All paid plans include analytics, automation, abandoned cart tracking, free gifts and offers, advanced display rules, and cart session monitoring. 14-day money-back guarantee on all plans.
Fast Cart Pricing:
- Free (WordPress.org): The complete plugin. No premium version exists.
| Caddy Free | Caddy Pro (Starter) | Fast Cart | |
|---|---|---|---|
| Annual Cost | $0 | $99 | $0 |
| Side Cart Features | Extensive | Extensive | Basic |
| Revenue Optimization | Yes (free shipping meter, recommendations, rewards) | Yes (all free + analytics, automation, abandoned cart) | No |
| Upgrade Path | Yes | N/A | No |
| Money-Back Guarantee | N/A | 14 days | N/A |
Bottom Line: Both plugins offer a genuinely free option. The difference is that Caddy’s free version is packed with revenue-driving features, and there is a clear upgrade path when your store is ready for analytics and automation. Fast Cart is free and will stay free, but what you see today is what you will always get.
5. Integrations and Compatibility
Caddy:
Caddy has been tested extensively with the WooCommerce ecosystem. Confirmed compatibility includes WooCommerce Subscriptions, Product Bundles, Elementor, Divi, GeneratePress, Flatsome, Astra, Kadence, OceanWP, and Storefront. HPOS support and block theme compatibility ensure Caddy works with the latest WooCommerce and WordPress standards.
Building on the Interactivity API and Store API also positions Caddy well for the future. As WordPress continues its modernization with these APIs, Caddy is already aligned with the direction of core development.
Fast Cart:
Fast Cart supports HPOS and block themes. Given its minimal footprint and limited feature set, it is unlikely to conflict with most themes and plugins. However, the plugin’s smaller install base (200+ active installs) means compatibility has been tested across fewer real-world configurations.
Bottom Line: Caddy’s larger install base and explicit compatibility testing with popular plugins and themes gives you more confidence that it will work with your specific stack. Fast Cart should work fine in most setups, but you are more likely to be the first to encounter an edge case.
6. Use Case Fit
The right plugin depends on what your store actually needs. Here is a clear breakdown.
Choose Caddy if you:
- Want your cart to actively help increase average order value
- Need product recommendations, a free shipping meter, or save for later, without paying for them
- Plan to grow and want analytics and automation available when you are ready
- Run a store with WooCommerce Subscriptions, Product Bundles, or other ecosystem plugins
- Want a plugin backed by 4,000+ active installs and a dedicated development team
- Care about conversion optimization, not just displaying cart contents
Choose Fast Cart if you:
- Need the absolute lightest possible cart plugin, measured in kilobytes
- Only need basic AJAX cart functionality: add, remove, change quantity
- Want a fully free plugin with no upsells, nag screens, or premium prompts
- Prefer a dead-simple setup with virtually no configuration required
- Are building a minimal store where extra cart features are genuinely unnecessary
- Value the principle of a focused, single-purpose tool over a feature-rich platform
Final Verdict
Fast Cart deserves respect for what it is: a clean, ultra-lightweight, completely free side cart that does exactly what it promises. If all you need is a basic AJAX cart that adds almost no weight to your site, it works. There are no hidden catches and no premium upsells.
But for most WooCommerce stores, basic is not enough.
Caddy is the stronger choice for any store that cares about revenue growth. Even the free version includes features that actively drive higher cart values: product recommendations, the free shipping progress meter, save for later, and coupon support. These are not cosmetic additions. They are proven conversion mechanics that directly impact your bottom line.
When your store is ready to get serious about optimization, Caddy Pro unlocks analytics that show you exactly what is working, abandoned cart tracking that captures lost revenue, and workflow automation that lets you create targeted offers without manual effort. That upgrade path does not exist with Fast Cart.
The real comparison is not Caddy vs Fast Cart. It is whether you want a cart that displays your products or a cart that helps you sell more of them.
Try Caddy Today
- Start free: Download Caddy from WordPress.org and get product recommendations, the free shipping meter, save for later, and more, at no cost.
- Explore Pro: Visit usecaddy.com to see how analytics, automation, and abandoned cart tracking can take your store further. Every plan includes a 14-day money-back guarantee.
