Email Validator
Validate any email address in one API call — syntax check, MX record verification, and disposable email detection. Get clear deliverability signals for every address.
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API Integration Guide
Learn how to integrate this API into your applications with code examples and detailed documentation.
/api/check-emailBase URL
https://www.apipick.comFull Endpoint
https://www.apipick.com/api/check-emailemailThe email address to validate
Example: user@example.comcURL Request
curl -X POST "https://www.apipick.com/api/check-email" \
-H "Content-Type: application/json" \
-H "x-api-key: YOUR_API_KEY" \
-d '{
"email": "user@example.com"
}'YOUR_API_KEY with your actual API keyJSON Response
{
"success": true,
"code": 200,
"message": "Email validation complete",
"data": {
"email": "user@example.com",
"valid": true,
"syntax_valid": true,
"mx_valid": true,
"disposable": false,
"domain": "example.com",
"normalized": "user@example.com",
"reason": null
},
"credits_used": 1,
"remaining_credits": 99
}✓Best Practices
- • Always include x-api-key header
- • Always handle errors gracefully
- • Validate input data before sending
- • Use HTTPS for secure communication
- • Cache responses when appropriate
ℹResponse Headers
- • Content-Type: application/json
- • x-api-key: Required for authentication
- • Status codes: 200 (success), 400 (error), 401 (unauthorized)
- • No rate limiting applied
Three Checks in One Call
Syntax Validation
Verifies RFC-compliant format, detects typos, and returns a normalized canonical form of the address.
MX Record Check
Performs a live DNS lookup to confirm the domain has active mail exchange records and can receive email.
Disposable Detection
Checks against a database of 50,000+ known disposable and throwaway email domains (Mailinator, Guerrilla Mail, etc.).
Perfect for These Use Cases
SaaS Registration
Block disposable emails at signup to prevent trial abuse and keep your user base genuine.
Marketing List Hygiene
Clean email lists before campaigns to improve deliverability rates and protect sender reputation.
Fraud Prevention
Identify throwaway addresses used in fraudulent signups, coupon abuse, and fake account creation.
AI Agent Enrichment
Use as an LLM tool to verify email quality inside autonomous lead research, CRM enrichment, and outreach automation pipelines.
ZeroBounce & AbstractAPI Alternative
Same validation quality — without the per-batch pricing wall or a 100-request monthly cap.
ZeroBounce | AbstractAPI | API Pick ✓ | |
|---|---|---|---|
| Free tier | 100 / month | 100 / month | 100 credits on signup |
| Free credits expire? | Monthly reset | Monthly reset | Never expire |
| Pay-as-you-go price | $24 / 3,000 emails | $14 / mo (10k) | $5 / 5,000 emails |
| Cost per 1,000 emails | ~$8.00 | ~$1.40 (monthly sub) | $1.00 |
| Syntax check | ✓ | ✓ | ✓ |
| MX record check | ✓ | ✓ | ✓ |
| Disposable detection | ✓ | ✓ | ✓ |
| No credit card to start | ✗ | ✗ | ✓ |
| AI agent / LLM ready | Partial | Partial | ✓ Native JSON |
The ZeroBounce problem
ZeroBounce charges $24 for just 3,000 verifications — that's $8 per 1,000 emails. For teams running any volume through a registration form or CRM enrichment pipeline, costs escalate fast. There's no true pay-as-you-go: you buy credits in bulk packs and unused ones don't roll over cleanly.
The AbstractAPI problem
AbstractAPI's free tier gives you only 100 requests per month — enough to prototype but nowhere near enough for any real workload. The moment you exceed that, you're forced onto a monthly subscription even if your usage is sporadic or bursty.
Response Fields
| Field | Type | Description |
|---|---|---|
| valid | boolean | true when syntax_valid and mx_valid are both true |
| syntax_valid | boolean | Email format passes RFC syntax rules |
| mx_valid | boolean | Domain has at least one active MX record |
| disposable | boolean | Domain is a known disposable/throwaway email service |
| domain | string | Extracted domain part of the email |
| normalized | string | null | Canonical lowercase, Unicode-normalised form |
| reason | string | null | Human-readable explanation when validation fails |
Rate Limits
Request Rate
60req / min
Per API key, per endpoint. Sliding 60-second window.
Concurrency
3concurrent
Max simultaneous in-flight requests per API key.
Response Headers
429 Too Many Requests
HTTP/1.1 429 Too Many Requests
Retry-After: 12
X-RateLimit-Limit: 60
X-RateLimit-Remaining: 0
X-RateLimit-Reset: 12
{
"error": "rate_limit_exceeded",
"message": "Rate limit exceeded: 60 requests/minute per API key. Retry after 12s.",
"retry_after": 12
}Frequently Asked Questions
Q: What is the difference between valid and mx_valid?
A: mx_valid only tells you the domain can receive email. valid combines syntax_valid and mx_valid — it is your go-to field when you simply want to know whether an address is deliverable. The disposable flag is returned separately so you can decide your own policy on throwaway addresses.
Q: Does the API send a test email to verify the mailbox?
A: No. The API performs DNS MX lookups but does not send any email or do SMTP probing. This means mailbox-level existence cannot be confirmed, but the domain-level deliverability check catches the vast majority of bad addresses without any privacy or spam concerns.
Q: Can AI agents call this API as a tool?
A: Yes. The endpoint takes a single email string and returns a flat JSON object — straightforward to define as an OpenAI function, Claude tool, LangChain tool, or any agent framework action. Ideal for autonomous lead enrichment and CRM hygiene pipelines.
Q: How current is the disposable email blocklist?
A: The blocklist is sourced from the community-maintained disposable-email-domains repository on GitHub (50,000+ domains). It is refreshed automatically on each server cold start.
Use Email Validator in Claude Code & AI Agents
Install the official Claude Code skill to validate emails directly inside your AI coding agent — no manual API calls needed. Works with Claude Code, Cursor, OpenAI Codex, and more.
Ask your AI agent naturally
Compatible platforms
Claude Code skill for APIpick Email Validator API
Performs syntax validation, MX record checks, and disposable email detection via natural language queries in any AI coding agent.