I Built a Browser Tool That Catches All 19 Shopify CSV Import Errors Before Upload

#shopify #webdev #csv #ecommerce

Shopify's CSV importer has three problems every developer eventually discovers:

Silent failures. It shows a green "Import successful" banner even when individual rows fail.
Cryptic messages. "Validation failed: An error occurred" — no row number, no column name, no hint.
No undo. You can't preview what will happen before you import, and you can't roll back.

I got tired of debugging CSV imports for migration projects, so I built CSVPreflight — a browser-based validator that catches errors before you upload.

How It Works

Everything runs in the browser. Your CSV never leaves your machine.

Drop a CSV file → 19 validation rules run automatically
Each error shows exact row number + column name + plain-English explanation
Auto-fix handles, booleans, URLs, and whitespace (Pro feature, $5/mo)
Download the clean CSV and import with confidence

The 19 Checks

Category	What It Catches
Handle format	Spaces, special chars, uppercase — auto-fix to valid slug
Required columns	Missing Handle, Title before upload
Duplicates	Duplicate handles and SKUs that silently skip rows
Prices	Non-numeric, negative, currency symbols
Booleans	`yes`/`no`/`1`/`0` → auto-fix to TRUE/FALSE
Images	Invalid URLs, missing protocols
Whitespace	Leading/trailing spaces that break matching
Variant structure	Option Name/Value pairing, orphan rows

...and 11 more.

Tech Stack

Zero dependencies on the client side. Pure HTML/CSS/JS with a Cloudflare Pages backend for the Stripe checkout. The validator engine is deterministic — no AI needed, so it runs in milliseconds on 10,000+ row files.

Why Not Just Use Matrixify?

Matrixify is great for power users managing massive catalogs. But for "I just need to upload this CSV without errors" — $20-200/mo and a steep learning curve is overkill.

CSVPreflight is free to validate. Pro is $5/mo. That's intentional — it does one thing and does it well.