Data Cleaning & Spreadsheets
How to Fix Malformed Email Addresses in Bulk Before Uploading to CRM
Priya Sharma
Lead Deliverability & Outreach Specialist
October 10, 2026 6 min read
TL;DR / Quick Summary
Fix malformed email addresses in bulk by stripping leading/trailing whitespace, standardizing to lowercase, replacing common TLD typos (.con to .com), and validating RFC 5322 compliance.
The 5 Most Common Email Errors in B2B Exports
1. Hidden whitespace tabs at the end of strings. 2. Domain typos (@gmai.com, @outlok.com). 3. Multiple addresses packed into a single CSV cell separated by commas. 4. Missing top-level domains. 5. Uppercase characters causing duplicate database keys.
Frequently Asked Questions
Can Olonyn split multiple emails in one cell?
Yes, our intelligent parser separates comma or semicolon delimited emails into structured secondary contact columns.
Written by Priya Sharma
Lead Deliverability & Outreach Specialist
Specializes in cold email inbox placement, SPF/DKIM/DMARC server infrastructure, and anti-spam deliverability algorithms.
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