Email Normalizer
Normalize email addresses in your browser: lowercase, strip Gmail dots and plus-aliases, trim whitespace, and remove duplicates.
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What is Email Normalizer?
Email Normalizer turns a messy list of addresses into a clean, deduplicated list you can import anywhere. It lowercases everything, removes plus-aliases, strips dots from Gmail local parts where they are insignificant, trims whitespace, and collapses duplicate rows — all with domain-aware rules that never mangle addresses on providers where those characters matter. Everything runs in your browser, so customer lists never leave your machine.
Key Benefits
- Clean lists in seconds — paste, pick a preset, copy
- Merge Gmail dot and plus-alias duplicates into one contact
- Domain-aware rules avoid false merges on other providers
- Line-by-line preview flags malformed addresses before import
- Fully offline — no uploads, no accounts, no tracking
Common Use Cases
- •Deduplicating a mailing list before a Mailchimp or SendGrid import
- •Cleaning sign-up exports where users registered with tagged aliases
- •Comparing two CRM exports for overlapping contacts
- •Preparing user lists for analytics where one person should count once
- •Auditing a newsletter list for malformed entries
How to Use the Email Normalizer
- Paste your list: Type or paste addresses into the input box, one per line, or click Load sample to try it.
- Pick a preset: Choose Gmail to strip dots and +tags, Outlook for +tags on Microsoft domains, or Basic for lowercase only.
- Toggle options: Enable Trim whitespace and Remove duplicates to match how you will import the list.
- Copy or download: Copy the normalized list or download it as a text file, then check the line-by-line preview for invalid rows.
Key Features
- Lowercases every address for case-insensitive comparison
- Strips +tag aliases for Gmail, Outlook, Hotmail, and Live domains
- Removes insignificant dots from Gmail/Googlemail local parts
- Deduplicates the list and reports how many duplicates were removed
- Flags structurally invalid lines in a line-by-line preview
Frequently Asked Questions
Are [email protected] and [email protected] really the same address?
Yes. Gmail ignores dots in the local part, so both deliver to the same inbox. This tool merges them when you use the Gmail preset. Other providers treat dots as significant, so the tool never strips them outside Gmail and Googlemail.
What does a plus-alias like [email protected] mean?
Anything after the plus sign is ignored by the mail server, so [email protected] and [email protected] are the same mailbox. People use tags to track where an address leaks from. The normalizer removes the tag so duplicate signups collapse into one row.
Is my email list uploaded anywhere?
No. Normalization runs entirely in your browser with plain string operations — nothing is sent to a server, logged, or stored. It keeps working offline once the page has loaded.
Does an invalid tag mean the address does not exist?
No. The tool only checks structure: one @ symbol, a non-empty local part, and a domain containing a dot. An address can pass this check and still be unregistered, and some exotic but valid addresses may be flagged. Always verify bounces with your mail provider.