Checkmail API API ID: 12379

Email verification API with real SMTP RCTP TO check, DNS, disposable, catch-all, and role-based detection in a single request.
Use this API from your AI agent via MCP
Works with OpenClaw, Claude Code/Desktop, Cursor, Windsurf, Cline and any MCP-compatible AI client.
Docs & setup
Create a skill by wrapping this MCP: https://mcp.zylalabs.com/mcp?apikey=YOUR_ZYLA_API_KEY

CheckMail verifies email addresses beyond basic syntax checks. One API call returns a full verification result: syntax validation (RFC 5322), DNS and MX record lookup, real SMTP handshake to confirm the mailbox exists, disposable domain detection (10,000+ known providers), catch-all detection, role-based address flagging (info@, admin@), free provider detection, and typo suggestions (gmial.com → gmail.com).

The API is a simple REST endpoint. One GET request with your email, one JSON response with everything. No SDK to install, no complex setup. Integrate in minutes with any language: Node.js, Python, PHP, Ruby, Go.

GDPR-safe by design: email addresses are never stored on disk, only SHA-256 hashes. Results are cached for 24 hours to reduce redundant SMTP probes. 

API Documentation

Endpoints


Verifies a single email address and returns a detailed JSON response covering syntax validation, MX record lookup, real SMTP handshake, disposable domain detection, catch-all detection, role-based address flagging, free provider detection, and typo suggestions. Only charges one credit for definitive results. Unknown results from unreachable mail servers are free. Results are cached for 24 hours.



                                                                            
GET https://pr132-testing.zylalabs.com/api/12379/checkmail+api/23393/verify+email
                                                                            
                                                                        

Verify email - Endpoint Features

Object Description
email [Required] The email address to check
Test Endpoint

API EXAMPLE RESPONSE

       
                                                                                                        
                                                                                                                                                                                                                                                                                                                                        {"checks":{"mx_found":true,"syntax":true,"free_provider":false,"catch_all":false,"disposable":false,"role_based":true,"smtp_valid":true},"typo_suggestion":null,"mx_host":"mail.op-email.eu","email":"[email protected]","status":"valid","cached":true,"ms":5}
                                                                                                                                                                                                                    
                                                                                                    

Verify email - CODE SNIPPETS


curl --location --request GET 'https://zylalabs.com/api/12379/checkmail+api/23393/[email protected]' --header 'Authorization: Bearer YOUR_API_KEY' 


    

API Access Key & Authentication

After signing up, every developer is assigned a personal API access key, a unique combination of letters and digits provided to access to our API endpoint. To authenticate with the Checkmail API simply include your bearer token in the Authorization header.
Headers
Header Description
Authorization [Required] Should be Bearer access_key. See "Your API Access Key" above when you are subscribed.

Simple Transparent Pricing

No long-term commitment. Upgrade, downgrade, or cancel anytime. Free Trial includes up to 50 requests.

🚀 Enterprise

Starts at
$ 10,000/Year


  • Custom Volume
  • Custom Rate Limit
  • Specialized Customer Support
  • Real-Time API Monitoring

Customer favorite features

  • ✔︎ Only Pay for Successful Requests
  • ✔︎ Free 7-Day Trial
  • ✔︎ Multi-Language Support
  • ✔︎ One API Key, All APIs.
  • ✔︎ Intuitive Dashboard
  • ✔︎ Comprehensive Error Handling
  • ✔︎ Developer-Friendly Docs
  • ✔︎ Postman Integration
  • ✔︎ Secure HTTPS Connections
  • ✔︎ Reliable Uptime

Checkmail API FAQs

The CheckMail API returns a JSON response containing detailed email verification results, including syntax validation, MX record lookup, SMTP validation, disposable domain detection, catch-all detection, role-based address flagging, free provider detection, and typo suggestions.

Key fields in the response include "email" (the verified email), "status" (valid/invalid), "checks" (detailed validation results), "typo_suggestion" (if applicable), "mx_host" (MX server), "cached" (cache status), and "ms" (response time in milliseconds).

The response data is structured as a JSON object. It includes a top-level email field, a status field, and a nested "checks" object that details various validation results. This organization allows for easy parsing and access to specific validation outcomes.

The API provides information on email syntax validity, MX records, SMTP validation, disposable domains, catch-all addresses, role-based addresses, free email providers, and suggestions for common typos, offering a comprehensive verification overview.

Data accuracy is maintained through real-time SMTP handshakes, DNS lookups, and a database of over 10,000 disposable domains. Additionally, results are cached for 24 hours to minimize redundant checks and improve response times.

Typical use cases include validating user sign-ups, cleaning email lists, preventing fraud, ensuring deliverability for marketing campaigns, and enhancing user engagement by filtering out invalid or disposable email addresses.

Users can customize their requests by specifying the email address they wish to verify in the GET request. The API does not require additional parameters, making it straightforward to use for single email verifications.

If results are partial or empty, users should check the "status" field for validity. An "unknown" status indicates the mail server was unreachable. Users can retry the request later or investigate the email address for potential issues.

The CheckMail API performs several validations, including syntax validation (RFC 5322), DNS and MX record checks, real SMTP handshake verification, and detection of disposable domains, catch-all addresses, role-based addresses, and free email providers. This comprehensive approach ensures a thorough assessment of the email address's validity.

The "status" field indicates the overall validity of the email address. It can return values such as "valid," "invalid," or "unknown." A "valid" status means the email passed all checks, while "unknown" suggests the mail server was unreachable, requiring further investigation or retries.

The "checks" object contains boolean values indicating the results of various validation checks. For example, "syntax" shows if the email format is correct, "mx_found" indicates if MX records exist, and "smtp_valid" confirms if the mailbox exists. This object provides detailed insights into the verification process.

The API includes a "typo_suggestion" field in the response, which offers corrections for common misspellings, such as suggesting "gmail.com" instead of "gmial.com." This feature helps users identify and rectify potential errors in email addresses before further actions.

The CheckMail API is designed to be GDPR-safe. Email addresses are never stored; instead, they are hashed using SHA-256. This approach protects user data while still allowing for effective verification through temporary caching of results for 24 hours.

The "mx_host" field provides the mail exchange server associated with the verified email address. Users can use this information to understand the email's routing and delivery capabilities, which can be useful for troubleshooting or optimizing email communications.

The API flags role-based addresses such as "info@", "admin@", "support@", and similar formats. This detection helps users identify non-personal email addresses that may not be suitable for targeted communications or user engagement.

The API checks against a database of over 10,000 known disposable email providers. If an email address matches one of these providers, it is flagged as disposable, helping users filter out temporary addresses that may not be reliable for ongoing communication.

General FAQs

Please have a look at our Refund Policy: https://zylalabs.com/terms#refund

To obtain your API key, you first need to sign in to your account and subscribe to the API you want to use. Once subscribed, go to your Profile, open the Subscription section, and select the specific API. Your API key will be available there and can be used to authenticate your requests.

You can’t switch APIs during the free trial. If you subscribe to a different API, your trial will end and the new subscription will start as a paid plan.

If you don’t cancel before the 7th day, your free trial will end automatically and your subscription will switch to a paid plan under the same plan you originally subscribed to, meaning you will be charged and gain access to the API calls included in that plan.

The free trial ends when you reach 50 API requests or after 7 days, whichever comes first. 

No, the free trial is available only once, so we recommend using it on the API that interests you the most. Most of our APIs offer a free trial, but some may not include this option.

 Yes, we offer a 7-day free trial that allows you to make up to 50 API calls at no cost, so you can test our APIs without any commitment. 

Zyla API Hub is like a big store for APIs, where you can find thousands of them all in one place. We also offer dedicated support and real-time monitoring of all APIs. Once you sign up, you can pick and choose which APIs you want to use. Just remember, each API needs its own subscription. But if you subscribe to multiple ones, you'll use the same key for all of them, making things easier for you.

Prices are listed in USD (United States Dollar), EUR (Euro), CAD (Canadian Dollar), AUD (Australian Dollar), and GBP (British Pound). We accept all major debit and credit cards. Our payment system uses the latest security technology and is powered by Stripe, one of the world's most reliable payment companies. If you have any trouble paying by card, just contact us at [email protected]

Additionally, if you already have an active subscription in any of these currencies (USD, EUR, CAD, AUD, GBP), that currency will remain for subsequent subscriptions. You can change the currency at any time as long as you don't have any active subscriptions.
The local currency shown on the pricing page is based on the country of your IP address and is provided for reference only. The actual prices are in USD (United States Dollar). When you make a payment, the charge will appear on your card statement in USD, even if you see the equivalent amount in your local currency on our website. This means you cannot pay directly with your local currency.
Occasionally, a bank may decline the charge due to its fraud protection settings. We suggest reaching out to your bank initially to check if they are blocking our charges. Also, you can access the Billing Portal and change the card associated to make the payment. If these does not work and you need further assistance, please contact our team at [email protected]
Prices are determined by a recurring monthly or yearly subscription, depending on the chosen plan.
API calls are deducted from your plan based on successful requests. Each plan comes with a specific number of calls that you can make per month. Only successful calls, indicated by a Status 200 response, will be counted against your total. This ensures that failed or incomplete requests do not impact your monthly quota.
Zyla API Hub works on a recurring monthly subscription system. Your billing cycle will start the day you purchase one of the paid plans, and it will renew the same day of the next month. So be aware to cancel your subscription beforehand if you want to avoid future charges.
To upgrade your current subscription plan, simply go to the pricing page of the API and select the plan you want to upgrade to. The upgrade will be instant, allowing you to immediately enjoy the features of the new plan. Please note that any remaining calls from your previous plan will not be carried over to the new plan, so be aware of this when upgrading. You will be charged the full amount of the new plan.
To check how many API calls you have left for the current month, refer to the 'X-Zyla-API-Calls-Monthly-Remaining' field in the response header. For example, if your plan allows 1,000 requests per month and you've used 100, this field in the response header will indicate 900 remaining calls.
To see the maximum number of API requests your plan allows, check the 'X-Zyla-RateLimit-Limit' response header. For instance, if your plan includes 1,000 requests per month, this header will display 1,000.
The 'X-Zyla-RateLimit-Reset' header shows the number of seconds until your rate limit resets. This tells you when your request count will start fresh. For example, if it displays 3,600, it means 3,600 seconds are left until the limit resets.
Yes, you can cancel your plan anytime by going to your account and selecting the cancellation option on the Billing page. Please note that upgrades, downgrades, and cancellations take effect immediately. Additionally, upon cancellation, you will no longer have access to the service, even if you have remaining calls left in your quota.
After 7 days, you will be charged the full amount for the plan you were subscribed to during the trial. Therefore, it's important to cancel before the trial period ends. Refund requests for forgetting to cancel on time are not accepted.
When you subscribe to an API free trial, you can make up to 50 API calls. If you wish to make additional API calls beyond this limit, the API will prompt you to perform an "Start Your Paid Plan." You can find the "Start Your Paid Plan" button in your profile under Subscription -> Choose the API you are subscribed to -> Pricing tab.
Payout Orders are processed between the 20th and the 30th of each month. If you submit your request before the 20th, your payment will be processed within this timeframe.
You can contact us through our chat channel to receive immediate assistance. We are always online from 8 am to 5 pm (EST). If you reach us after that time, we will get back to you as soon as possible. Additionally, you can contact us via email at [email protected]

Related APIs