DievioMail Merge Preview
Preview an email template against your own CSV rows before sending. Find unknown variables and empty cells, with optional fallback values for missing personalization.
How to use this tool
- Paste a CSV with named columns.
- Write a template using matching double-brace fields.
- Preview all rows and fix unresolved or empty fields.
A worked example
Input
Template: Hi {{first_name|there}}
first_name: emptyOutput
Hi there
The explicit fallback is used for an empty value. Without a fallback, the unresolved field remains visible and produces a warning.
What the result means
Fix rows with unresolved fields before using the template in a sender. Fallbacks replace empty or absent values only when you explicitly provide a fallback in the tag.
Nothing is sent. Names match CSV headers exactly. Syntax: {{field}} or {{field|fallback}}. Plain text only; previews do not execute HTML.
Frequently asked questions
Which personalization syntax is supported?
Use {{field}} for an exact CSV header or {{field|fallback}} for a supplied fallback. Header names are case-sensitive. Incomplete and nested tags are rejected.
Does previewing send messages or upload recipients?
No. Messages are rendered locally against your supplied CSV. You can export previews for review, but the tool does not connect to a mailbox or sending platform.
Is this free, and are my inputs uploaded?
Use this tool without an account, subscription or credits. Processing and file exports run in your browser; the tool does not upload your inputs or send emails. Clear inputs to remove the current data. Inputs are not saved when you reload the page.
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