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Checkers · Validation tools

Email validator

Check a whole list of email addresses at once for formatting problems — missing symbols, stray characters, and typo'd domains.

Runs in your browser No signup Free forever Format check only — no mailbox ping

Email addresses

5 lines
0
Checked
0
Valid
0
Invalid

Paste one email per line and check them — each line gets its own pass or fail, with a reason if it fails.

More checkers

Related tools you might need next

Email malformed checker Password strength checker SPF record checker Dead link checker

All 5 checkers

What gets flagged

Six formatting rules

Missing @ symbol

Every address needs exactly one @ separating the local part from the domain.

Multiple @ symbols

multiple@@symbols.com is rejected — a valid address has exactly one.

Missing domain extension

An address needs a . after the domain name — user@example alone isn't enough.

Starts or ends with @

@invalid.com and invalid.email@ are both missing the part on the other side.

Invalid characters

Most punctuation outside . @ - and word characters isn't allowed. A plain space is a special case — see the FAQ.

Typo'd TLD

Common substitutions like .c0m, .n3t, .0rg and .1nfo are flagged with the domain you probably meant.

How it works

Three steps, no account

1

Paste your list

One address per line. Works for five addresses or five hundred — there's no server round-trip to wait on.

2

Check the summary

The count of valid and invalid addresses appears instantly, before you scroll to see which ones failed.

3

Fix what's flagged

Each failing line shows the specific reason, so you're not left guessing which character broke it.

FAQ

Common questions

Does this confirm the email actually exists?
No — it checks formatting only. A correctly formatted address can still belong to no one. Confirming a mailbox is live requires contacting the recipient's mail server directly, which this tool intentionally doesn't do.
Is my list of addresses sent anywhere?
No. Checking runs entirely in your browser using a regular expression — nothing is uploaded, logged, or stored, which matters if the list you're checking is a customer or contact database.
How many emails can I check at once?
There's no fixed limit — since nothing leaves your browser, a few thousand lines check just as fast as five. Very large pastes (tens of thousands of lines) are limited only by your device's memory.
Why did a real email address get flagged?
The rules here follow the common, practical shape of an email address rather than the full formal spec, which technically allows some unusual characters almost no real provider accepts. A space in the local part (before the @) is always rejected, for example — real mail systems don't accept it either, even though the formal spec has a quoted-string exception for it.
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Related

People who used this also used

Email malformed checker A narrower single-address check for one-off lookups.
SPF record checker Check whether a domain's outbound mail is set up correctly.
Dead link checker The same bulk-list, per-row pattern — for URLs instead of emails.
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Email Validator/Malformed Checker

Our Email Validator helps you verify the format of email addresses. Check multiple emails at once and identify common formatting issues instantly.

How to Use the Validator

1. Enter Emails

  • Input one email per line
  • Paste multiple addresses
  • Bulk validation
  • Instant checking

2. View Results

  • Valid email list
  • Invalid email list
  • Error explanations
  • Statistical summary

3. Common Checks

  • @ symbol presence
  • Domain validation
  • TLD verification
  • Format compliance

Key Features

Validation Checks

  • Syntax verification
  • Domain format
  • Special characters
  • Common mistakes

Error Detection

  1. Missing Elements

    • @ symbol
    • Domain name
    • TLD (Top-level domain)

  2. Format Issues

    • Invalid characters
    • Multiple @ symbols
    • Malformed structure

  3. Common Mistakes

    • Number substitutions
    • Missing dots
    • Invalid domains

Use Cases

1. Data Cleaning

  • Mailing lists
  • User databases
  • Contact imports
  • Bulk verification

2. Form Validation

  • Registration forms
  • Contact forms
  • Newsletter signup
  • User input

3. Data Management

  • Database cleanup
  • List verification
  • Export validation
  • Quality control

Technical Features

  • Real-Time Validation: Instant results
  • Bulk Processing: Multiple emails
  • Detailed Feedback: Error explanations
  • Statistical Analysis: Results summary

Why Use Our Validator

1. Comprehensive Checks

  • Multiple validations
  • Common error detection
  • Format verification
  • Detailed feedback

2. User-Friendly Design

  • Simple interface
  • Clear results
  • Bulk processing
  • Instant feedback

3. Practical Benefits

  • Time saving
  • Error prevention
  • Quality assurance
  • Data accuracy

Understanding Email Validation

Common Issues

  1. Format Problems

    • Missing components
    • Invalid characters
    • Wrong structure
    • Typos

  2. Domain Issues

    • Invalid TLDs
    • Missing dots
    • Number substitutions
    • Fake domains

Best Practices

  1. Input Cleaning

    • Remove spaces
    • Check formatting
    • Verify structure
    • Validate domains

  2. Validation Process

    • Syntax check
    • Domain verification
    • TLD validation
    • Format compliance

Remember: Proper email validation helps maintain data quality and ensures reliable communication channels.