Cart scraping: why you need to protect your Shopify inventory

Here’s the deal: if you’re running a Shopify store, cart scraping is probably happening to you, whether you realize it or not. It’s simple, it’s sneaky, and it can cost you big time. Think this is just a small-time issue? Think again.

As developers, we actually stumbled upon this problem when merchants started reporting strange errors with Shopify functions. Shopify began showing detailed logs, and we saw bots maxing out inventory numbers for various products in the cart—triggering input size errors. That’s when we realized it was a much bigger issue. Bots were quietly scraping inventory data, and no one was doing anything to stop it.

Let’s look at a concrete example. Even stores like Kylie Cosmetics aren’t safe from this. All someone needs is the variant ID for a product, and they can use that to check your stock levels, no hacking required. Take this example from Kylie Cosmetics—by using a URL like this:

https://kyliecosmetics.com/cart/46601157083378:999999

You can see exactly how many units of the Lip & Cheek Blush Tint - Summer Feeling are left in stock—1,744 units, to be exact. Just like that, the data is out in the open. Imagine hundreds of bots doing this over and over across your entire product line.

This is your inventory, product sales trends, and restock cycles—exposed. Competitors can use this data against you, and they will. So if you’re not taking action, you’re leaving yourself wide open.

Why this matters

Here’s why cart scraping is a direct threat to your business:

1. Competitors know exactly how well your products are selling. They can see the exact numbers on your bestsellers and use this data to reverse-engineer how you’re acquiring customers—whether through ads, organic search, or SEO. Once they have that intel, they’ll try to hijack your SEO efforts, target your customers, and steal traffic that should be going to your store.
2. They can study your restock patterns. By tracking when and how often you restock certain products, competitors can optimize their own operations. They’re not just looking at you—they’re doing this to multiple competitors to get a clear picture of the market. Essentially, they’re building their strategy using your internal data.
3. They’ll run ads against you. If they see that your high-selling products are running low, they’ll seize the opportunity. Competitors can run ads for alternatives to your products, specifically targeting the customers who would’ve bought from you if you weren’t out of stock. You lose the sale, they gain a customer.

How to protect your store: order limits

Here’s how you fight back: order limits. Setting a cap on how many items someone can add to their cart can stop these bots from getting accurate data. They’ll try to add a huge number of units to check your stock, but if you’ve limited the cart to, say, 20 units, their data becomes useless.

That’s where DC Order Limits comes in. It lets you set limits on how many of each product variant can be added to a cart. So when bots try to load up on your bestsellers to scrape your inventory, they’ll hit that max limit, and their scraping efforts will fall flat.

Setting it up is easy. Here’s the link to get started: DC Preorders & Order Limits.

Make scraping even harder with smart inventory tactics

There’s another way to make bots’ lives harder: use Shopify’s "Continue selling when out of stock" feature, but with a twist. Let’s say you set your products to keep selling until the inventory drops below 20 units. This way, bots can’t get a precise read on your stock levels—they’ll think the product is still available, even when it’s low.

You can automate this with Shopify Flow so you don’t have to constantly manage it yourself. It’s a simple step that can make a big difference in keeping your inventory data safe from scrapers.

Why you need to act now

Cart scraping is bad enough, but it becomes a real nightmare during high-traffic times like Black Friday, Cyber Monday (BFCM), and the Christmas season. This is when your store is busiest, and this is when bots will be working overtime. If your competitors know exactly how much stock you have left during a major sale, they can steal sales right out from under you.

By setting order limits with DC Order Limits and using smart strategies like "Continue selling when out of stock," you’re taking back control of your store. And you need to do it now, before the busiest shopping days hit.