# Shopify-pet · Post 2 — Tip

**Where to post:** LinkedIn, Shopify Discord, pet-business Facebook
groups, niche e-comm newsletters' "tip" inboxes.

**Format:** ~150 words.

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## Title

The hidden character in your Shopify customer export that breaks Klaviyo imports (and how to spot it)

## Body

Open your Shopify customer export. Look at the email column.

Some of your emails have an invisible character in them — usually a zero-width space (`U+200B`) or a non-breaking space (`U+00A0`) — copied in from a customer typing on their phone. Visually identical to a normal email. Klaviyo treats them as different addresses, so:

- Your "duplicate customer" check passes when it shouldn't
- The customer gets emailed twice
- Your unsubscribes don't propagate (the unsub list has the *clean* email; the next campaign send reaches them via the *invisible-char* email)

Spot it: in Excel, paste your email column into a single cell with `=LEN(A2)` next to it. Anything that's longer than the visible character count has a hidden char in it.

If you want to automate the cleanup (plus phone normalization, dedupe, the whole pre-Klaviyo scrub), I built a $49 desktop tool: datatools.app/shopify-pet. Local — your customer list never leaves your computer.

— {{your-name}}
