Email Validation & Disposable Domain Detector

Fast, production-grade email validation with real-time MX record lookups, RFC 5322 syntax checks, and disposable / temporary email domain detection.

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🎯 What it does

This Actor validates email addresses using three layers of checks, returning a structured JSON result for each email:

Layer	What it checks	Method
Syntax	RFC 5322 compliance	Regex + length rules
DNS / MX	Domain can receive email	Async DNS lookup against Cloudflare 1.1.1.1, Google 8.8.8.8, Quad9 9.9.9.9
Disposable	Domain is a temporary / throwaway provider	Curated 636-domain blacklist + heuristic detection
Typo	Domain is a misspelling of a major provider	Levenshtein distance ≤ 2 against 20+ top providers

✨ Features

• ✅ RFC 5322 syntax validation — catches malformed emails (not-an-email, user@@example.com, etc.)
• ✅ Real MX record lookup — async DNS, returns primary MX host, IP address, and priority
• ✅ 636-domain curated disposable blacklist — Mailinator, TempMail, GuerrillaMail, 10MinuteMail, YOPmail, and 631 more
• ✅ Heuristic detection — catches disposable domains not in the blacklist via:
  • High-abuse TLDs (.tk, .gq, .cf, .ml)
  • Keyword matching (temp, trash, throwaway, disposable, 10minutemail, ...)
  • MX-pattern recognition (custom domains pointing at disposable infrastructure)
  • High-entropy random subdomain detection (Shannon entropy)
• ✅ Typo detection — catches user@hootmail.com and suggests user@hotmail.com
• ✅ Cache — results cached for 24h (Redis primary, in-memory fallback)
• ✅ Async & parallel — validates 1,000 emails per run with bounded concurrency
• ✅ Low latency — p95 < 350ms (cache miss), < 5ms (cache hit)

📥 Input

The Actor accepts a JSON object with the following fields:

Field	Type	Required	Default	Description
emails	array of strings	✅	—	List of email addresses to validate (max 1,000 per run)
check_mx	boolean	❌	true	Set to false to skip MX lookups (syntax + disposable only, much faster)
detect_disposable	boolean	❌	true	Set to false to skip disposable detection

Example input

{
  "emails": [
    "alice@gmail.com",
    "spam@mailinator.com",
    "user@hootmail.com",
    "not-an-email",
    "bob@nonexistent-xyz-domain-12345.com"
  ],
  "check_mx": true,
  "detect_disposable": true
}

📤 Output

Each validated email is pushed to the default dataset as a separate item:

{
  "email": "someone@mailinator.com",
  "valid": false,
  "disposable": true,
  "reason": "Blacklist",
  "domain": "mailinator.com",
  "syntax_valid": true,
  "mx_host": "mail.mailinator.com",
  "mx_ip": "23.239.11.30",
  "mx_info": "Using MX pointer mail.mailinator.com from DNS with priority: 10",
  "domain_typo_detected": false,
  "suggested_correction": null,
  "execution_time_ms": 142,
  "cache_hit": false
}

Field reference

Field	Type	Description
email	string	The email address that was checked
valid	boolean	true if syntactically valid AND has MX/A records AND not disposable AND no typo
disposable	boolean	true if domain is a known or heuristic disposable provider
reason	string|null	"Blacklist", "MX Pattern", "Heuristic", or null
domain	string|null	Lowercased domain part of the email
syntax_valid	boolean	true if RFC 5322 syntax is valid
mx_host	string|null	Primary MX hostname
mx_ip	string|null	IPv4 of primary MX host
mx_info	string|null	Human-readable MX resolution summary
domain_typo_detected	boolean	true if domain is a typo of a major provider
suggested_correction	string|null	Corrected email when typo detected
execution_time_ms	integer	Server-side processing time in ms
cache_hit	boolean	true if served from cache

💡 Use cases

1. Signup form validation

Block disposable emails at signup to prevent abuse and ensure deliverable onboarding emails.

2. Lead list cleanup

Run a CSV of leads through this Actor before a marketing campaign. Filter out:

• Invalid syntax (will bounce)
• No MX records (will bounce)
• Disposable (will never convert)
• Typos (correct them and salvage the lead)

3. Fraud detection

Flag accounts signing up with temp-mail providers for manual review.

4. Email list hygiene

Periodically re-validate your subscriber list to remove addresses whose domains have lost MX records.

🔧 How it works

┌─────────────────────────────────────────────────────────┐
│                    Input (emails[])                       │
└─────────────────────────────┬───────────────────────────┘
                              │
                              ▼
              ┌───────────────────────────────┐
              │      OrchestratorAgent         │
              │  (cache lookup → fan-out)      │
              └───┬───────────────────────┬───┘
                  │                       │
                  ▼                       ▼
    ┌──────────────────────┐  ┌──────────────────────┐
    │ ValidationEngine     │  │  DisposableIntel     │
    │  - RFC 5322 syntax   │  │  - Blacklist match   │
    │  - Async DNS MX      │  │  - MX pattern        │
    │  - Typo detection    │  │  - Heuristics        │
    └─────────┬────────────┘  └──────────┬───────────┘
              │                          │
              └────────────┬─────────────┘
                           ▼
              ┌──────────────────────┐
              │  Push to dataset     │
              └──────────────────────┘

📊 Performance

Path	p50	p95	Notes
Cache hit	0–5 ms	< 10 ms	In-memory or Redis GET
Cache miss (valid email)	50–150 ms	< 250 ms	Parallel DNS + blacklist
Cache miss (disposable)	20–100 ms	< 200 ms	Blacklist short-circuits
1,000 emails (bulk)	—	~30 sec	Bounded concurrency (20)

🧪 Tested

• 107 unit + integration + live DNS tests pass
• 96 real-world emails tested (Gmail, Yahoo, Outlook, iCloud, Proton, international providers, disposable providers, typos, invalid syntax)
• 50 concurrent requests: p95 = 170ms
• Zero correctness issues in extended testing

📚 Same logic as the RapidAPI version

This Actor shares its core engine with the Email Validation & Disposable Domain Detector API on RapidAPI. If you need a real-time HTTP API (vs. batch Apify runs), use the RapidAPI version. If you need to process thousands of emails in batch, use this Actor.

📝 License

MIT