Verify at Scale.
50,000 req/min.
Enterprise API built for high-volume pipelines. Process millions of addresses with full catch-all resolution and real-time webhooks.
Trusted by Global Clients and Agencies
50K req/min throughput
Horizontally scalable infrastructure with automatic rate adjustment and burst handling.
Real-time Webhooks
Get results as they complete with configurable webhook endpoints and retry logic.
99.9% Uptime SLA
Enterprise SLA with dedicated infrastructure and named support for high-volume customers.
Batch & Streaming
Upload CSV batches or stream individual verifications in real-time via WebSocket.
Full Catch-All Coverage
Every address gets our full 40-signal analysis, not just syntax checks.
SDKs Included
Python, Node.js, Go, and PHP client libraries with full documentation and examples.
Simple, Powerful API
Start verifying in minutes. Our REST API is designed for developer simplicity without sacrificing the depth of our 40-signal catch-all engine.
High-Volume Verification Without the Bottleneck
Quick Answer
Bulk email verification sends a list of addresses through a multi-layer validation pipeline and returns a deliverability verdict for each one. EmailAddress.ai processes 50,000 verifications per minute, resolves catch-all domains with active inbox signals, and returns results in JSON or CSV format with full status codes and confidence scores for suppression and CRM sync.
EmailAddress.ai is an enterprise email verification platform used by marketing operations teams, data engineers, and email service provider (ESP) integrations to maintain list hygiene at scale. The Bulk Verification API is a RESTful endpoint with client libraries for Python, Node.js, Go, and PHP, designed to integrate into existing data pipelines without custom infrastructure.
The core differentiator is catch-all domain resolution. Standard bulk verifiers mark all catch-all addresses as Unknown and exclude them from results, typically discarding 20 to 40 percent of a B2B list. EmailAddress.ai applies 40 active inbox signals per address on catch-all domains, returning a deliverability confidence score rather than a blanket Unknown status.
Results include a primary status (Valid, Invalid, Catch-All, Risky, Unknown) and a sub-status code for routing logic. Over 10 sub-status codes cover disposable addresses, role-based accounts, spam traps, SMTP errors, and catch-all types, giving suppression and CRM workflows the granularity needed to make per-address decisions at scale.
Who Uses the Bulk Verification API
Clean email lists before campaign sends to protect sender reputation and deliverability rates. A list with more than 2% hard bounces triggers ESP throttling and blacklist risk. Running lists through the API before every major send removes invalid and risky addresses at scale.
Validate new contacts at ingestion before they enter the CRM. Integrate the API into your data pipeline so every contact record created or imported is verified before it reaches sales reps or triggers automated sequences.
EmailAddress.ai is built for platform integration. The RESTful API, webhook callbacks, and batch file upload support let ESP teams run verification inline for their customers without adding manual steps or external tooling to the workflow.
Verify HCP email lists before sending to physicians, pharmacists, or healthcare administrators. The catch-all resolution engine handles hospital and health system domains, which standard verifiers skip, giving healthcare senders accurate deliverability data on their full list.
Every Address Goes Through 6 Checks
Checks correct email format, character sets, and domain structure. Catches typos and malformed addresses before querying any external server.
Verifies the domain exists and has valid MX records. Flags disposable domains, role-based addresses, and known spam traps.
Connects to the recipient mail server and tests acceptance without sending a message. Returns server response codes for deliverable, rejected, or deferred.
Identifies catch-all domains and routes them to the inbox signal resolution step rather than returning Unknown.
Checks 40 active inbox signals to confirm recent send or receive activity on catch-all addresses.
Returns primary status plus sub-status code and confidence score for granular suppression or CRM routing logic.
Frequently Asked Questions
What is bulk email verification?
Bulk email verification tests a large list of email addresses against mail servers and inbox signal data to determine which addresses are deliverable, invalid, or risky before sending a campaign. It prevents bounces, protects sender reputation, and improves campaign deliverability. EmailAddress.ai processes up to 50,000 addresses per minute with catch-all resolution included.
What is the throughput of the Bulk Email Verification API?
The API processes up to 50,000 verification requests per minute on enterprise infrastructure with horizontal scaling and burst capacity. A list of 100,000 addresses takes approximately 2 minutes. A list of 1,000,000 addresses takes under 20 minutes. Large batch jobs can be submitted via file upload and results delivered via webhook.
What status codes does the API return?
The API returns a primary status (Valid, Invalid, Catch-All, Risky, Unknown) and a sub-status code for routing. Sub-statuses include: none (clean), disposable, role-based, smtp-error, smtp-timeout, mail-server-full, does-not-accept-mail, catch-all-email, mailbox-not-found, possible-spam, and unroutable-ip. Full documentation is available at emailaddress.ai/resources/api-docs.
Does the bulk API resolve catch-all domains?
Yes. EmailAddress.ai applies 40 active inbox signals to catch-all addresses instead of returning them as Unknown. Standard verifiers skip catch-all domains entirely, discarding 20 to 40 percent of a typical B2B list. EmailAddress.ai returns a confidence score for each catch-all address so you can apply your own deliverability threshold.
Can I integrate the API with my CRM or ESP?
Yes. Native integrations are available for HubSpot, Salesforce, Marketo, and Mailchimp. The RESTful API connects to any system supporting HTTP requests. Webhooks deliver results asynchronously without polling. Direct CRM sync automatically updates contact records with verification status and confidence scores.
What is the accuracy rate for bulk verification?
EmailAddress.ai returns 98%+ accuracy on Valid results, which are actively verified via SMTP handshake. Catch-All results return a confidence score from 0 to 1 so you can filter by your own acceptable deliverability threshold. The API supports a confidence cutoff parameter to automatically exclude results below a specified score.
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Enterprise infrastructure. Developer-friendly API. Full catch-all resolution.