How it works
Paste your email template with {{variable}} placeholders in Step 1, then paste your contact list CSV in Step 2. Click Preview emails and the tool renders the first 20 merged emails exactly as recipients would see them, with any issues flagged inline.
Paste your template
Use {{variable_name}} placeholders anywhere in the subject or body.
No variables detected yet. Add placeholders like {{first_name}} to your template.
Paste your contact list
Paste CSV or spreadsheet rows. Include a header row so the tool can match columns to variables.
Column headers should match your template variables. For example, a column named first_name fills in {{first_name}}. Headers are matched case-insensitively.
Preview merged emails
See the first 20 emails exactly as they will be sent, with issues flagged inline.
Paste a template and contact list to get started.
Fill in Steps 1 and 2, then click Preview emails.
What it flags
The tool catches the mistakes that turn a polished cold email sequence into an embarrassing send. If the CSV itself needs cleanup before you preview the merge, run it through the cold email CSV checker.
- Empty values, where a blank cell renders as "Hi ," or "Quick idea for ,"
- Placeholder values like N/A, undefined, or null sitting in cells that should hold real data
- Broken variables, meaning a placeholder that looks like a typo of a real column, such as {{frist_name}} when first_name exists
- Variables with no matching column anywhere in the contact list, so they never fill in
- Columns in the contact list that the template never references
- Duplicate suffixes, like a merge that turns Acme Inc. into "Acme Inc. Inc."
A practical review flow
Preview the merge after the CSV is cleaned and before the sequence goes into a sending tool. The goal is to catch the mistakes a normal spreadsheet scan misses: empty greetings, repeated company suffixes, awkward sentence fragments, and template variables that look right until they render.
- Scan the issue summary first and fix broken variables before reading individual previews.
- Read the first few rendered emails out loud, especially the greeting and first sentence.
- Check rows with empty, placeholder, or unusually long fields before exporting.
- Open the CSV next to the preview so each issue becomes a row edit, not a vague warning.
- Run one final preview after edits so fixed columns did not create a new mismatch.
What it does not do
This tool renders the merge and shows you the result. It flags what breaks at render time: empty greetings, placeholder values, broken variables, unused columns, and repeated company suffixes. It stops at the preview. It doesn't send the campaign, confirm that each address can receive mail, or measure spam risk. It won't invent a missing role or company, and it doesn't connect to your sending platform, so nothing here touches your live sequence. Fix the template and list, then paste them back into the tool you send from.
Privacy
The merge happens entirely in your browser. Your template and contact list aren't uploaded anywhere, and the rendered previews exist only on this page. Close the tab and nothing is kept.
Questions, answered.
Nothing, and no account is needed. Paste a template and a contact list, and you can preview all 20 rows and export the issues at no charge.