Build the bundle you thought was impossible
Complex bundles, made simple. Native to Shopify checkout and fulfillment.
Customizers, mix-and-match kits, gift sets, custom pricing: grow AOV with bundles built exactly the way you want them.
Trusted by high-volume Shopify brands
Why Flex Bundles
Complex on the storefront
Design the bundle experience your brand needs, with no templates in the way.
- Any bundle you can design
- Full control over how your bundles look, behave, and are priced. Build the custom logic and UX your bundles need on a developer-friendly foundation, with no rigid templates.
- Built for AI-assisted development
- Bundles run on a small, documented Cart API contract, so coding agents like Claude Code and Cursor can build custom bundle experiences straight from the docs.
- Bundles Admin API
- Create and update bundles from your own scripts and systems: sync from a PIM, build seasonal bundles in bulk, and wire bundle management into the catalog tooling you already run.
Simple behind the scenes
Every bundle runs through native checkout and fulfillment like any other order.
- Expanded line items in checkout
- Bundles expand into their individual line items at checkout, so customers, your team, and your fulfillment tools all see exactly what's in every order.
- Real-time inventory sync
- Bundles work natively with Shopify, so inventory stays accurate in real time at every location and never drifts out of sync across your bundles and their components.
- Maps to ShipStation & your 3PL
- Every bundle carries custom data attributes that map to exactly what tools like ShipStation and your 3PL need, so orders flow through to fulfillment cleanly.
- Every sales channel
- Bundle orders from TikTok Shop and the Shop app expand into their components just like orders from your online store.
- Multi-currency pricing
- Bundle prices convert in multi-currency checkouts, so international customers pay exactly what they saw.
Built to grow
Find the offers that sell, then scale them without limits.
- A/B price testing on bundles
- Full control over bundle pricing lets you run true A/B price tests to find the offers that convert best.
- Full-history analytics & exports
- See how every bundle performs with unlimited order history and AOV lift per bundle, then take the numbers anywhere: CSV export, an analytics API for your dashboards, and order-level data stored in your own store.
- One-click bundle reorder
- Customers can rebuild a previous bundle from their saved selections, turning a good first order into a repeat purchase.
- Unlimited bundles & bundle sales
- No caps. Create as many bundles as you want and sell as many as you can, on a plan that scales with you instead of throttling growth.
Built for AI agents
Tell your agent what bundle you want
Flex Bundles is built to be driven by AI coding tools. Connect Claude Code, Cursor, or any MCP client to your store, and your agent sets up bundles and builds the storefront for them from your real configuration.
- An MCP server for your bundles
- Your agent can create and update bundles, look up products, and check the exact add-to-cart request against a bundle's rules.
- Docs agents can read
- Every docs page is available as plain Markdown, and the full set is at /llms.txt.
- Guardrails on the server
- Each bundle can carry server-side pricing rules, so generated code that sends the wrong price is stopped at checkout.
Connect
claude mcp add --transport http flex-bundles \
https://api.flexbundles.com/mcp \
--header "Authorization: Bearer fxb_your_api_key"Then ask
- Create a build-your-own bundle on the Gift Box product, priced by component sum, with a minimum of 3 items and a maximum of 6.
- Build a mix-and-match section for the Build Your Box bundle. Enforce its rules in the UI and show the server's error message if the add fails.
- How did the Starter Kit bundle do over the last 30 days compared to orders without bundles?
An agency used Claude and the Flex Bundles API to put 87 fixed bundles live on a client's store in 30 minutes. Read the story.
Case studies
How Pashion Footwear made bundles their #1 acquisition tool
The brand behind the world's only convertible high heel grew bundle sales 1,275% in three months, with zero paid advertising.
Read the case study →
How Giordano's built its DTC business on bundles
The iconic Chicago deep-dish brand made bundles the core of its direct-to-consumer experience on Shopify, driving strong average order value growth.
Read the case study →What our customers say
This redesign alone has increased our bundle sales by over 450% in just over 2.5 months! The app is an absolute must for any store wanting to customize a bundle experience. The team is very responsive with any issues or questions you may have.
— Pashion Footwear
Robbie built the exact bundle experience we wanted and was so great to work with. They built us an awesome custom BYOB bundle experience and set up about 100 fixed bundles. Our AOV with bundles was well over double our non-bundle AOV.
— Craftspring
Flex Bundles has been a major value driver for our business. Whether we're setting up one-click bundles, dynamic bundles, or limited-time promotional bundles, the app makes it incredibly easy to execute. The setup is intuitive, fast, and reduces the operational overhead typically required for bundle management.
— Puffco
Flex Bundles has been a critical app for Giordano's DTC website, as we sell our products almost entirely in bundled formats. They did an outstanding job delivering bundle functionality that's easy to edit and is driving meaningful revenue. Robbie has been awesome to work with — outstanding service.
— Giordano's Nationwide Shipping
This app is great right out of the box, but Robbie and the team took it a step further and were able to create a BYOB bundle feature and page. This has been really successful for us on our site. Highly recommend!
— Michael Malul
Flex Bundles fills the gaps that Shopify's native bundles are missing. It's highly customizable, easy to use, and does exactly what we need. The customer service is outstanding: knowledgeable, friendly, quick to respond, and truly easy to work with.
— Perrin Performance
Flex Bundles & Robbie have been a game-changer for our store. The app is incredibly flexible and solved major challenges we were having with ShipStation integration and inventory management. It does exactly what other solutions couldn't.
— The Tuttle Twins
Flex Bundles is hands-down the best bundling app we've tried. It runs natively on Shopify, so setup and fulfillment are seamless. Great variety of bundle types, clean layouts, and easy theme integration. Super customizable — perfect for devs, too.
— W&P