How to convert email addresses to lowercase in a csv
- Step 1Export your contact list as CSV — Download from your CRM, checkout tool, or form platform.
- Step 2Drop the file into Case Converter — Select the Email column for conversion.
- Step 3Choose lowercase — Apply lowercase to the Email column only.
- Step 4Download and import into your ESP — Use the normalised CSV for Mailchimp, Klaviyo, or your chosen email platform.
Frequently asked questions
Does email case actually matter for deliverability?+
Email servers treat addresses as case-insensitive, but your CRM and ESP may not. Lowercase normalisation prevents duplicate records being created.
Can I lowercase just the email column without touching names?+
Yes. Choose only the Email column in the column selector. Other columns are untouched.
Does this change the subject line or email body?+
No. This tool only modifies CSV cell values in the columns you select.
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