Duplicate SKU Sync Master alternative for shared stock

At a glance

	Duplicate SKU Sync Master	OneShelf
How it works	When the stock of a SKU changes, the app copies the new level to every listing with the same SKU, in near real time.	One base stock holds the real count. Each linked listing gets its Shopify quantity from it.
Price	$5 to $20/month, by your Shopify plan. The full sync plans are $10 to $40/month. 7-day free trial.	Free for up to 10 base stocks. Pro is $9.99/month with no limit and a 30-day free trial.
Online and at POS	Yes. The listing says it works for the same SKUs online and at POS.	Yes. A sale online or at the register takes from the same base stock.
Kits and bundles	The listing says you can build bundles with SKUs.	Yes. A listing can use several base stocks, with a number per sale such as 2 or 0.5.
Stops a cart before payment	The listing does not mention a checkout check.	Yes, if you turn it on. The checkout rule stops a cart that needs more base stock than you have.
Preview before it changes stock	The listing does not mention a preview or test mode.	Yes. Preview mode writes nothing to Shopify until you press Go live.
Several stores	No. The listing says it matches stock at all locations in one store.	No. OneShelf works inside one store.
On the App Store since	January 6, 2021	October 5, 2026
Rating	3.3 stars from 16 reviews	New. See the listing.

The Duplicate SKU Sync Master facts are from its App Store listing on November 4, 2026. "The listing does not say" means that the fact is not on the listing. It does not mean that the app cannot do it.

What reviewers report

These are recent reviews with 1 to 3 stars, from the Duplicate SKU Sync Master reviews. One review is one store's experience. Read the full reviews and the developer's replies before you decide.

1 star · March 31, 2025

“products that have been out of stock for weeks magically have new inventory, resulting in oversold products.”

1 star · March 29, 2025

“some items have not synced properly for over five months, preventing us from selling these products.”

When Duplicate SKU Sync Master is the better choice

Your listings are the same item with the same SKU, and you only need their numbers to stay equal.
You need the same stock level matched at several locations.

When OneShelf fits better

Your listings share an item but not a SKU, such as one blank tee behind many designs.
A listing uses more than one item, or a part of one, such as a kit or a 5 ml decant.
You want a cart that asks for too much to stop before payment.

How to move from Duplicate SKU Sync Master to OneShelf

Export your inventory from Shopify. Go to Products, then Export. Keep the file as a record of your numbers today.
Install OneShelf. It starts in Preview mode, so it writes nothing to Shopify.
Create a base stock for each shared item. Count the real shelf. Link the listings that sell it. OneShelf shows each listing's quantity now and after, before you save.
Watch a few real orders in Preview mode. The Activity page shows what OneShelf would take for each order.
Turn off the sync in Duplicate SKU Sync Master for the listings you linked. Only one app should set the stock of a listing. OneShelf warns you if a listing changes outside OneShelf.
Press Go live. Then turn on the checkout rule in Settings, if you want a cart that asks for too much to stop before payment.
Uninstall Duplicate SKU Sync Master when you are sure. Check a few listings after, and compare them with your export.

If you need help with the move, write to support@oneshelf.app. A real person answers.

Questions

Is OneShelf a good alternative to Duplicate SKU Sync Master?

It is if your listings share one real stock in one store, such as blanks, materials, or bulk stock. If you need to share stock between several stores, OneShelf does not do that.

Can I keep Duplicate SKU Sync Master installed while I try OneShelf?

Yes. OneShelf starts in Preview mode and writes nothing to Shopify. Before you press Go live, turn off the sync in Duplicate SKU Sync Master for the listings you link. Only one app should set the stock of a listing.

Will I lose my stock numbers when I move?

Export your inventory from Shopify first, so you have a record. When you create a base stock, OneShelf shows each listing's quantity now and after, and it changes nothing until you save.

How much does OneShelf cost?

OneShelf is free for up to 10 base stocks. Pro is $9.99/month with no limit, and it has a 30-day free trial.

Try OneShelf in Preview mode

OneShelf gives your listings one base stock. Every sale, online or at the register, takes from that one number. It is free for up to 10 base stocks.

Install on Shopify Open the demo store

The demo store password is shesta.

Duplicate SKU Sync Master is a product of Thalia Tech. OneShelf is not related to Thalia Tech. If a fact on this page is wrong or old, write to support@oneshelf.app and we will correct it.