Variant-deleting Option columns
Update a product with variants but omit the Option1 Name / Value columns, and Shopify replaces every variant with one default — deleting the rest. We flag multi-variant products at risk.
Free · No signup · Runs in your browser
Free Shopify CSV Validator
Most CSV checkers tell you if your import will fail. This one catches the worse problem: an import that succeeds and quietly corrupts your live catalog — deleted variants, blanked-out fields, duplicated products. Check your file before you upload.
100% in-browser — your file is never uploaded, stored, or seen by us.
What it checks
The mistakes that pass the import — then break your catalog.
Each of these is documented Shopify behavior. The import won't error; it just does exactly what the file says, not what you meant.
Blank cells that overwrite
When overwriting by handle, a column that's present but blank erases the existing value. An empty Vendor or Body (HTML) cell can wipe real data on every matching product.
Missing or mismatched handles
The Handle column is how Shopify matches rows to products. A blank, changed, or non-URL-safe handle either edits the wrong product or creates a duplicate.
Encoding & smart quotes
Shopify expects UTF-8. Curly quotes and the wrong encoding garble characters and can trigger an "illegal quoting" error. We scan for BOMs, smart quotes, and mojibake.
Structure & format
Wrong delimiter, ragged rows with too many or too few columns, unbalanced quotes, non-numeric prices, non-integer inventory — the format slips that shift your data into the wrong fields.
File-size limit
Shopify's product CSV import has a maximum file size. We check yours against it so a large catalog export doesn't bounce at the upload step.
A successful import is the dangerous one
A failed import is annoying but safe — nothing changed. The imports that hurt are the ones that go through. The Shopify product CSV isn't really a spreadsheet; it's a list of instructions applied straight to your live catalog, with no dry-run preview and no native undo. When an instruction is ambiguous, the importer doesn't pause to ask — it picks an interpretation and runs it across every matching row.
That's why a single missing column can delete variants, and a single blank cell can blank a field on hundreds of products, without ever showing an error. This validator exists to catch those instructions before you hand them to Shopify. For the full mechanics behind each trap, read our guide to why Shopify CSV imports corrupt products.
Still back up first. A validator lowers the odds of a bad import, but it can't undo one. Until Shopify itself has an undo, export the products you're about to change and keep that file — it's your only rollback path with a raw CSV.
Catch the risk here. Prevent it for good.
This free tool flags the danger one file at a time. SheetBridge is being built to remove it entirely — two-way Google Sheets ↔ Shopify sync designed to snapshot your catalog before every write and roll back in one click. It's pre-launch, with no live customers yet. Join the waitlist and be first in.
No spam — one email when your invite is ready. We store only your address (Privacy Policy), and we read every reply.
Shopify CSV validator — FAQ
How do I validate a Shopify CSV before importing?
Drop your product CSV into the tool above. It parses the file in your browser and checks it against the Shopify product-CSV rules that most often corrupt a catalog — missing Option columns, blank cells that overwrite fields, mismatched or blank handles, non-UTF-8 encoding, and the file-size limit — then lists exactly which rows are at risk. Nothing is uploaded; the check runs locally on your device.
Why did my Shopify CSV import delete variants?
When you update a product that has variants, Shopify's CSV format requires the Option1 Name and Option1 Value columns. Per Shopify's documentation, if those columns are missing the import creates a single default variant and deletes the existing variants. This validator flags multi-variant products whose Option columns are missing or blank before you import.
Does a blank cell in a Shopify CSV overwrite my data?
It can. With "Overwrite products with matching handles" selected, Shopify's docs state that a non-required column that is present but left blank overwrites the existing value with blank, while a column omitted from the file entirely is left untouched. So an empty Vendor or Body (HTML) cell can erase real data. The validator flags product-level columns that are present but blank.
Is this Shopify CSV checker really free, and is my file uploaded?
It is free, with no signup and no row limit. Your file is never uploaded: the validation runs entirely in your browser using JavaScript, so the CSV — including a full live catalog — stays on your device and is never sent to a server. You can confirm this in your browser's network tab: loading results makes no upload request.
Can I undo a Shopify CSV import if it goes wrong?
As of 2026, Shopify's admin has no native undo for a product CSV import — once it begins it can't be cancelled, and there's no history of past imports to roll back to. The standard safeguard is to export a backup CSV of the affected products before importing. This validator helps you catch problems beforehand, but a backup is still your only rollback path with a raw CSV import. See how to undo a bulk edit in Shopify.