Syntax Validation
Catches malformed addresses and common typos before deeper checks.
Clean Lists at Scale
Bulk Email Verifier
Upload a CSV or XLSX list, process each unique address once, and review valid, risky, invalid, and unknown results. Mailthentic keeps ambiguous provider and catch-all responses visible instead of converting them into false certainty.
Comprehensive Checks
What the Bulk Verifier Checks
Every email in your list passes through the same multi-layered verification engine.
Domain & MX Verification
Confirms domain existence and active mail exchange records.
Disposable Email Filtering
Detects temporary email services that create throw-away addresses.
Catch-All Domain Detection
Identifies servers configured to accept mail for any address, flagging uncertain results.
Role-Based Identification
Flags generic addresses like info@, admin@, and support@ with lower engagement potential.
SMTP Recipient Evidence
When enabled and available, adds recipient evidence without sending mail. Ambiguous responses remain visible.
How Bulk Email Verification Works
Upload CSV or XLSX
Select a supported file. Mailthentic detects a likely email column, normalizes addresses, and processes each unique address once.
Parallel Processing
Emails are verified in parallel with real-time progress tracking. Monitor job status from your dashboard.
Download Clean Results
Export results segmented by valid, risky, invalid, and unknown status, then apply your consent and sending policy.
Choosing a Tool
What to look for in a bulk email verifier
Bulk email checkers can use different evidence and handle uncertainty differently. Review these operational details before choosing one.
Does it tell you the truth about catch-all domains?
A catch-all domain accepts a random control address, so SMTP cannot confirm the target mailbox. Mailthentic keeps that uncertainty visible so you can segment the result and use acquisition or engagement evidence.
Does it charge you for duplicates?
Mailthentic normalizes and deduplicates the email column before processing, so each unique address is checked once. Keep your source rows for CRM reconciliation.
Does it explain why an address failed?
"Invalid" is not an answer. You need to know whether the syntax was malformed, the domain has no MX record, the mailbox was rejected at the SMTP layer, or the address is a disposable or role-based account. Mailthentic returns the reason, the SMTP response code, and a confidence score for every row.
Can it handle greylisting without guessing?
Many mail servers deliberately defer unfamiliar connections. Mailthentic can retry eligible temporary responses rather than turning a deferral into an invalid result.
Do you get your data back in a usable shape?
Mailthentic provides CSV or XLSX results that can be filtered by valid, risky, invalid, and unknown status. Keep the complete result set as an audit record.
Built for Scale
Bulk email verification software that handles real lists
Bulk email verification, mass email verification, batch email verification, and email list verification usually describe the same input pattern: checking multiple addresses in one job. They do not mean sending email to the list.
Mass email verification is not the same job as checking one address. A list reaches many mail systems with different rate limits, greylisting rules, and recipient behavior. Excessive probing can produce throttling and ambiguous answers.
Mailthentic queues work, groups shared MX infrastructure for throttling, and retries eligible deferrals. Temporary responses remain unknown until the workflow has enough evidence to classify them.
The dashboard reports asynchronous job status and progress. Wait for completion before treating the export as the final result set.
Free and Paid
Is there a free bulk email verifier?
Eligible new accounts receive 250 signup credits. Free accounts can verify up to 100 unique addresses per bulk job, subject to their remaining balance and the current runtime settings. No credit card is required to create the account.
Uploaded files and results are stored while the application processes and retains the job. Review the privacy policy and use only contact data you are authorized to process.
If you only need to check a single address, use the free email checker, no account required.
Choose the workflow that matches the input
| Workflow | Use it for | What happens |
|---|---|---|
| Bulk upload | Existing CSV or XLSX lists | Asynchronous processing with reviewable exports |
| Single checker | One address under investigation | DNS-only signals without signup |
| API | Signup, import, or application automation | Creates jobs that your integration polls |
| CRM workflow | Contacts already held in a supported platform | Live connectors where listed, otherwise CSV export and re-import |
Need the preparation and result-handling detail? Read the complete bulk email verification guide.
256-bit SSL Encrypted
No Emails Sent During Verification
No Data Reselling, Ever
Multi-Signal Verification
Frequently Asked Questions
What file formats are supported for bulk upload?
Mailthentic accepts CSV and XLSX. It detects a likely email column, normalizes addresses, and processes each unique address once.
How many emails can I verify at once?
The limit depends on your account tier, credits, subscription plan, and current settings. The product shows the applicable per-job limit. Mailthentic does not advertise an unlimited file size.
Are duplicate emails counted against my credits?
No. Mailthentic automatically deduplicates your list before processing begins, so you only pay for unique email addresses verified.
How long does bulk verification take?
Processing time depends on list size, mail-server behavior, retries, and the active verification settings. The dashboard reports the job status and progress. Mailthentic does not publish a fixed completion time.
Can I download results as CSV?
Yes. Download CSV or XLSX output and filter by valid, risky, invalid, or unknown status.
Explore More
Related Verification Tools
Email Verification
Review one address with syntax, DNS, MX, risk, and available SMTP evidence, then use the status guide to interpret it.
DNS Email Validation
Fast domain-level validation using MX, SPF, and DMARC checks without SMTP connections.
Domain Health Check
Audit your sending domain's published SPF, DKIM, and DMARC configuration.
Verification by Provider & Use Case
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