Why did my Shopify inventory import update nothing or set the wrong stock?

1. Your inventory CSV

The inventory export from Shopify admin (Products → Inventory → Export), edited in a spreadsheet. Product data stays on your device.

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Choose a file or paste the text, then click Check file.

Result

Rows with findings

The rules, and what they leave out

• Matching. Each row needs a Handle (lowercase letters, digits and hyphens) and a Location. Two rows with the same handle, option values and location give the importer two quantities for one stock record.
• The quantity column. The importer applies On hand (new) (older exports: Available (new)). A near miss such as Quantity, Qty or Stock is flagged because it can be ignored. A blank cell means no change.
• Quantities are whole numbers. Text, fractions, a thousands comma and spreadsheet errors are errors; a negative figure or a jump of ten times or more is a warning, because only you know whether it is real.
• Locations spelled with different capitals or spaces in one file are flagged; use the spelling Shopify shows.
• Excel damage. A SKU such as 4.01E+12 means Excel read it as a number and the digits are gone. Format the column as Text before editing.
• Safe fixes change only the delimiter, the spelling of known headers, stray spaces around a handle, SKU, location or quantity, and a trailing .0 on a whole-number quantity. It never changes a quantity's value, never resolves a duplicate and never touches a title or a column Shopify marks not editable.
• Not checked: that Shopify will accept the file today, that a handle exists in your store, that a location exists, stock movement since the export, and anything Shopify changes in its importer. Import a few rows first.

Common questions

Why did my Shopify inventory import update nothing or set the wrong stock?

The usual causes are a quantity column that is not named exactly On hand (new) (a header like Quantity or Stock is ignored), blank cells in that column (blank means no change), quantities written as text such as 12 pcs, fractions, or numbers with a thousands comma that split into two cells, an extra zero that makes a tenfold jump, two rows for the same variant and location so one quietly wins, a handle retyped with capitals or spaces so it matches no product, a location spelled differently from the one in Shopify, and an Excel save that turned long SKUs into scientific notation. This tool tests each of them and names the line.

Does a clean CSV mean the stock counts are right?

No. The tool checks formatting only. The import sets stock to the figures in the file, so a count taken hours ago can overwrite sales and receipts since the export. Export fresh just before editing and import a few rows first. A clean result is not a promise that Shopify will accept the file.

Why did my SKUs turn into 4.01E+12?

Excel treats a long run of digits as a number and shows it in scientific notation; once saved the original digits are lost. The tool flags it but cannot restore them. Re-export from Shopify with the column formatted as Text.

What does Apply safe fixes change?

Only things with one reasonable reading: the delimiter, the spelling of known headers, stray spaces and a trailing .0 on a whole number. Every change is listed with its line. It never changes a quantity's value.

Is it safe to put my product data into a web page?

The page runs in your browser, the file is read locally and nothing is uploaded; a test in the code asserts there are no network calls.