Documentation

Install the app and get your first limit live.

• What Nex Validator does Nex Validator sets minimum and maximum order limits on Shopify and blocks checkout when a cart breaks one. How the pieces fit together.
• Install and enable the app embed Install Nex Validator from the Shopify App Store and switch on the theme app embed so storefront quantity locking works.
• Create your first limit Build a working order limit end to end — pick the limit type, set the value, write the message, activate, and test it at checkout.
• The dashboard What each part of the Nex Validator dashboard does — setup status, rule summary, the two rule builders, and the guided tour.
• Plans and what is included What each Nex Validator plan includes, which features are Premium-only, and how the free trial works.

Set minimum and maximum quantities and amounts.

• Order limits The nine order limits you can set — cart quantity, cart amount, product and collection — and how to pick the right one.
• Minimum cart quantity Require a minimum number of items in the cart before customers can check out — for packing efficiency, build-your-own boxes and wholesale.
• Maximum cart quantity Cap the total number of items per order to protect stock during flash sales, drops and ticketed events.
• Minimum order amount Require a minimum cart value before checkout — the standard way to stop orders that cost more to fulfil than they earn.
• Maximum order amount Cap total cart value at checkout — used to limit fraud exposure and to route large orders through a quote instead.
• Minimum product quantity Require customers to buy at least a set number of a specific product — for custom printing, wholesale cases and perishables.
• Maximum product quantity Cap how many of one product a customer can buy in an order — the standard defence for limited drops and anti-reseller policies.
• Minimum collection quantity Require a minimum number of items from a Shopify collection before checkout — for wholesale catalogues, bundles and sample packs.
• Maximum collection quantity Cap how many items a customer can buy from a collection — for limited ranges, regulated categories and event merchandise.
• Product bulk limit Use product metafields to sell in fixed multiples, or set per-product minimums and maximums in bulk without listing every product by hand.

What the customer sees when a limit blocks them.

• Messages What a customer sees when a limit blocks them, where the message appears, and how to write one that recovers the sale.
• Write a custom message Replace the default block message with one that tells the customer exactly what to change.
• Show the message on the cart page Surface the limit message on the cart page instead of only at checkout, and tune it for themes that render carts differently.
• Multilingual messages Show the limit message in the customer’s language, with a default for everyone else. A Premium feature.

Storefront quantity locks versus checkout blocking.

• How enforcement works Nex Validator enforces limits in two independent layers — a storefront quantity lock and a checkout block. What each needs, and why only one is automatic.
• Lock the quantity selector Stop customers choosing an invalid quantity on the product page by driving the quantity input from a product metafield.

Conditional limits on the Premium plan.

• Advanced rules Apply a limit only in certain situations — by country, customer, dates or what is in the cart. A Premium feature.
• Match type Whether every condition must match or just one — and why adding conditions can make a rule fire more often, not less.
• Conditions Every condition an advanced rule can check — cart value, customer, location, products, quantities and dates.
• Build an advanced rule Create a limit that only applies in certain situations — conditions, match type, the limit itself, and the message.

Edit, pause, move and organise what you have built.

• Managing rules The Active Order Limits list — editing, enabling and disabling, deleting, and how many rules you can have.
• Import and export rules Move a rule between stores, or keep a backup before a risky edit, using the export and import actions in the rule editor.

Every rule type, plan limits and platform constraints.

• Reference Every rule type at a glance, what each one checks, and where to read more.
• Limits What Shopify caps, what your plan caps, and how to tell which one you have hit.
• Shopify limitations What Shopify itself allows and forbids for checkout validation — where it runs, the 25-function ceiling, and why POS is excluded.
• Glossary The terms used across these docs, the app and Shopify — and which of them mean the same thing.

A limit is not behaving the way you expect.

• Troubleshooting A limit is not behaving the way you expect. Start here to find which symptom you have.
• Limit is not blocking checkout A rule is saved but customers can still check out with a cart that breaks it.
• Message not showing Checkout is blocked but the customer sees no message, or sees the default instead of yours.
• Quantity picker not locked The product page still lets customers choose any quantity even though a limit is set.
• App embed not active You enabled the app embed but the dashboard still reports it as off.
• Rule will not save A rule refuses to save or enable — usually a missing title, a locked feature, or Shopify’s 25-validation ceiling.
• Works at checkout but not in cart Checkout blocks correctly but the cart page or drawer shows nothing.
• Works for me but not for customers Your test passes and real customers still get through, or get blocked when they should not.