Several add-ons, very little space.
Dense product rows — image, title, price, Add. Paging only when it's needed.
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2 Exactly what your shopper sees — at the moment they're ready to buy.
The Checkout Ninja tag only marks the block in this preview — it never appears in your live checkout.
"Fantastic app, highly recommended. We've been using it for years — a long list of checkout customisations suited to our store. A must-have for all your Shopify checkout needs."
How to add Quick Add Upsell to Shopify checkout
Install Checkout Ninja from the Shopify App Store, open the checkout editor, and drag the Quick Add Upsell block into the section where you want it. Then configure it in three steps. No theme code, no checkout.liquid, and it survives every Shopify update because it runs on Checkout Extensibility.
Pick the add-ons
Hand-pick products in the order you want them, or let Shopify's Related and Complementary recommendations fill the list.
Set the density
Choose how many products to pull in total and how many show per page. Paging controls — dots or a counter — only appear when the list overflows.
Enable variant picking
The per-product variant selector only ever renders for products that actually have more than one variant, and sold-out options grey out rather than disappear.
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How many products can I list?
You set both the total pulled in and the number shown per page. Keep the visible count low — a dense list of three or four converts better than a wall of ten.
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What happens to sold-out variants?
They stay visible but greyed out. Hiding them silently makes the picker feel broken when a shopper is looking for a size that exists.
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Should I use this or the standard Upsell block?
Use Quick Add when you have several comparable add-ons. Use Upsell or Featured Upsell when one offer is clearly the right one to push.
Build the rest of your checkout.
Featured Upsell
A single hero recommendation — big image, full details, one prominent Add button.
See the block Conversion BoostersPromo Banner Upsell
Your banner image up top, curated recommendations directly beneath it.
See the block Conversion BoostersUpsell
One-tap product recommendations at checkout — by tag, collection or value. +6% AOV.
See the blockInstalled by these templates
All templates →Add the Quick Add Upsell block today.
Every block + every feature, on a 3-day trial. No card. Live before your next order.