What does 'missing fallback' mean?

If a token has no default value and the recipient's record is missing the field, you send 'Hi !' to those readers. The validator flags every token without a fallback and shows the exact syntax to add one for the ESP you selected.

How do you detect typos?

We compute Levenshtein distance from each token to the canonical list (first_name, last_name, email, company, city, etc.). Distance 1 or 2 from a known token but not a perfect match gets flagged as a likely typo.

🔧 Merge-tag validator

Personalisation token validator

Paste your email. Find every {{first_name}}, *|FNAME|*, %recipient.first%, [%FIRSTNAME%]. Catch missing fallbacks and typos before they hit production.

6 ESP syntaxes Typo detection Browser-only

FAQ

Frequently asked questions

Which ESPs are supported?

Mailchimp, Klaviyo, Iterable, Customer.io, ActiveCampaign, generic Liquid, Salesforce.

What is a fallback?

A default value that renders when the recipient's field is empty. Without it, you send "Hi !" to readers missing the data.

How are typos detected?

Levenshtein distance to the canonical token list. Distance 1-2 from a known token but no exact match gets flagged.

Free?

Yes - 100% client-side.

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