See every email before you send it

Paste rows from Google Sheets and your template. Catch the "Hi ," emails, the typos and the bad addresses first.

Your sheet and template

Rows (with header)

Subject

Body

Email column

Paste a few rows and a template, or try the example.

Template looks good? Pick a tool to send it.

Compare Gmail mail merge and cold email tools for small businesses.

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What the previewer checks

One broken field can turn a personal email into an obvious mass mail. These are the mistakes it looks for.

Unknown fields

A {{field}} with no matching column. Mail merge tools usually leave it blank, so "Hi {{Frist Name}}" becomes "Hi ,".

Empty values

The column exists, but this row has nothing in it. The sentence around it may stop making sense.

Bad or missing emails

Rows with no address or one that can't be valid. These bounce, and bounces hurt your sender reputation.

Duplicates

The same address on two rows means the same person gets your email twice.

Long subjects

After merging, subjects over about 60 characters get cut off on phones.

Want to know whether the addresses actually exist? The Smart Email Verifier add-on checks them inside Google Sheets. Not sure how many to send a day? Try the cold email volume calculator.

Frequently Asked Questions

What placeholder format does this use? ▾

Double curly braces around a column header, like {{First Name}}. Matching ignores capital letters and extra spaces, so {{first name}} works too. This is the format Makeinfo Simple Mail Merge and many other mail merge add-ons use.

How do I paste rows from Google Sheets? ▾

Select your header row and the rows below it, copy, and paste into the box. Sheets copies them as tab-separated text, which the previewer reads directly. Comma-separated CSV works as well.

Does this send any emails? ▾

No. It only shows what each email would look like. Nothing is sent, uploaded or stored. Everything runs in your browser.

Does it check whether an email address really exists? ▾

No. It only checks that the address looks valid. To find out whether a mailbox actually exists before you send, use an email verifier like the Smart Email Verifier add-on for Google Sheets.