Email Validation API
Real-Time Email Validation
A fast, reliable REST API that verifies email addresses in under 50ms. Detect disposable emails, catch typos, check MX records, and score risk before bad data enters your system.
<50ms
Response Time
99.9%
Uptime SLA
100k+
Disposable Domains
15+
Validation Checks
Live Preview
See Real-Time Email Validation in Action
Try our API right now — enter any email and see how Mailchk validates it in real-time.
Test any email instantly
API Features
10 Email Verification Checks in One API Call
Each email goes through multiple validation layers to give you a complete picture of its quality.
Disposable Detection
Checks against a constantly updated database of disposable and temporary email providers to catch throwaway addresses.
MX Record Lookup
Queries DNS for MX records to verify the domain exists and is configured to receive email. Results are cached for performance.
Deliverability Score
Returns a numeric 0-100 deliverability score based on weighted risk factors, giving you a single metric for email quality.
Provider Detection
Identifies the email provider (Gmail, Microsoft 365, Yahoo, ProtonMail, etc.) from MX records for deeper validation insights.
SPF & DMARC Checks
Verifies domain authentication by checking SPF and DMARC DNS records. Flags domains with missing or misconfigured policies.
Typo Detection
Detects 90+ common domain typos (like gmial.com → gmail.com) and returns "did_you_mean" suggestions in the response.
Syntax Validation
Validates email format against RFC standards and provider-specific rules (Gmail 6-30 chars, Yahoo 4-32 chars, etc.).
Role Account Detection
Flags role-based emails like info@, admin@, support@ that typically have lower engagement rates.
Risk Scoring
Calculates a risk score (low, medium, high, critical) based on multiple factors including TLD risk, authentication, and more.
DNSBL Blacklist Check
Checks MX server IPs against DNS blacklists (Spamcop, Barracuda, DroneBL) to detect servers associated with spam.
Intelligent Detection
AI-Powered Disposable Domain Discovery
Our proprietary AI agent continuously crawls the web, discovering and classifying new disposable email providers the moment they appear — so your protection never falls behind.
Step 01
Real-Time Web Crawling
Our AI agent autonomously scours the open web — forums, directories, domain registrars, and underground communities — identifying newly registered domains that exhibit disposable email characteristics.
Step 02
AI Classification Engine
Each discovered domain is fed through a multi-signal classification model that analyses DNS patterns, registration metadata, hosting infrastructure, and behavioural fingerprints to determine disposable intent.
Step 03
Instant Protection
Verified disposable domains are pushed to our global detection layer within minutes. Every API call benefits from the latest intelligence — no manual updates, no stale blocklists.
110,000+
Domains Indexed
24/7
Continuous Scanning
<1hr
New Domain Detection
Zero-Day
Threat Coverage
How It Works
Integrate Email Verification in Minutes
Get Your API Key
Sign up for free and get your API key instantly. No credit card required.
Send a Request
Make a simple GET or POST request with the email you want to validate.
Get the Result
Receive a detailed JSON response with validity, risk score, and flags.
$ curl "https://api.mailchk.io/v1/check?email=j.smith+promo@gmail.com" \
-H "X-API-Key: YOUR_API_KEY"
{
"email": "j.smith+promo@gmail.com",
"domain": "gmail.com",
"valid": true,
"disposable": false,
"scam_domain": false,
"mx_exists": true,
"blacklisted_mx": false,
"free_email": true,
"did_you_mean": "",
"risk_score": "low",
"deliverability_score": 95,
"spf": "pass",
"dmarc": "pass",
"email_provider": "Gmail",
"normalized_email": "jsmith@gmail.com",
"is_aliased": true,
"alias_type": "plus_addressing",
"risk_factors": [
"free_provider"
]
}Lightning Fast
Blazing fast response times
Our globally distributed infrastructure delivers validation results in milliseconds, not seconds. While competitors make you wait, Mailchk returns accurate results before your users even notice.
Edge-optimized infrastructure
Servers in 12+ regions for minimal latency
Cached domain intelligence
Pre-computed data for instant lookups
Async processing
Non-blocking validation for maximum throughput
Average Response Time
10x faster than the industry average
Start Verifying Emails for Free
Sign up and get 200 free validations. No credit card required.