Spreadsheets
MergeMail uses your spreadsheet as the recipient list for every campaign. Each row becomes one email, and each column becomes a variable you can use in email bodies, subject lines, and document templates.
Supported Formats
- XLSX — Microsoft Excel (Office 2007+). The most reliable format. Multi-sheet files are supported; MergeMail uses the first sheet by default.
- CSV — Comma-separated values. UTF-8 encoding recommended. Files with BOM (byte-order mark) are handled correctly.
Maximum file size: 10 MB. For larger lists, split them into multiple datasets and run separate campaigns.
Column Normalization
MergeMail normalizes column headers into safe variable names. This means you can use natural-language headers in your spreadsheet without worrying about capitalization or spacing.
| Original column header | Normalized variable name |
|---|---|
| First Name | first_name |
| Last Name | last_name |
| Email Address | email_address |
| e_mail | |
| Phone Number | phone_number |
| Date of Birth | date_of_birth |
| Certificate ID | certificate_id |
| Membership # | membership_ |
| Amount (₦) | amount_ |
Normalization rules: lowercase all characters → replace spaces with underscores → strip special characters except underscores.
Email Column Detection
MergeMail automatically detects the email address column by looking for column names (after normalization) that match common patterns: email, email_address, e_mail, recipient_email, email_id, etc.
If your email column has an unusual name, you will be prompted to select it manually during dataset setup.
Validation Rules
MergeMail validates the spreadsheet during upload and reports issues before you proceed:
- Email validity: All values in the detected email column must be syntactically valid email addresses. Rows with invalid emails are flagged (but not silently skipped).
- Duplicate emails: Duplicate email addresses generate a warning. You can choose to skip duplicates or keep all rows.
- Empty rows: Completely empty rows between data rows are ignored.
- Column count consistency: Rows with a different number of columns than the header row are flagged.
- Character encoding: Non-UTF-8 characters in CSV files are re-encoded where possible. Characters that cannot be converted are replaced with a placeholder.
Worked Example
Here is a minimal spreadsheet for a certificate delivery campaign:
| Full Name | Course Title | Completion Date | Certificate ID | |
|---|---|---|---|---|
| Adaeze Okonkwo | adaeze@example.com | Data Analysis | 2024-11-15 | CERT-0001 |
| Emeka Nwosu | emeka@example.com | Web Development | 2024-11-15 | CERT-0002 |
| Fatima Bello | fatima@example.com | Project Management | 2024-11-22 | CERT-0003 |
After upload, these columns become available as variables: full_name, email, course_title, completion_date, certificate_id.
Tips for Clean Data
- Put headers in row 1 with no merged cells in the header row.
- Avoid blank rows between data rows.
- Use consistent date formats (ISO 8601 preferred: YYYY-MM-DD).
- For columns that contain numbers you want to display as text (e.g. "007"), format the cell as Text in Excel before exporting.
- Save as
.xlsxrather than.xls(legacy format).