Mailboxlayer Check API
The Check API from Mailboxlayer — 1 operation(s) for check.
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OpenAPI Specification
openapi: 3.2.0
info:
title: Mailboxlayer Check API
version: 1.0.0
description: Mailboxlayer offers a simple REST-based JSON API enabling you to thoroughly check and verify email addresses right at the point of entry into your system.
servers:
- url: https://apilayer.net/api
security:
- AccessKeyQuery: []
tags:
- name: Check
paths:
/check:
get:
summary: Validate
description: Perform an email validation for a single email address.
operationId: checkEmail
parameters:
- $ref: '#/components/parameters/access_key'
- $ref: '#/components/parameters/email'
- $ref: '#/components/parameters/smtp'
- $ref: '#/components/parameters/catch_all'
- $ref: '#/components/parameters/format'
- $ref: '#/components/parameters/callback'
responses:
'200':
description: Successful validation result (single object). Service-level errors (empty/invalid `email`, plan restrictions) are also returned here with HTTP 200 and a `success:false` ApiError body.
content:
application/json:
schema:
oneOf:
- $ref: '#/components/schemas/EmailValidationResponse'
- $ref: '#/components/schemas/ApiError'
examples:
default:
value:
email: support@mailboxlayer.com
did_you_mean: ''
user: support
domain: mailboxlayer.com
format_valid: true
mx_found: true
smtp_check: true
catch_all: false
role: false
disposable: false
free: false
score: 0.92
service_error:
value:
success: false
error:
code: 210
type: no_email_address_supplied
info: 'Please specify an email address. [Example: support@mailboxlayer.com]'
'401':
$ref: '#/components/responses/Unauthorized'
'403':
$ref: '#/components/responses/Forbidden'
'404':
$ref: '#/components/responses/NotFound'
'422':
$ref: '#/components/responses/ValidationError'
'429':
$ref: '#/components/responses/RateLimitReached'
'500':
$ref: '#/components/responses/InternalError'
'503':
$ref: '#/components/responses/Maintenance'
tags:
- Check
components:
parameters:
format:
name: format
in: query
required: false
schema:
type: integer
enum:
- 0
- 1
description: Set to 1 for human-prettified JSON output (useful for debugging; increases payload size).
example: 0
smtp:
name: smtp
in: query
required: false
schema:
type: integer
enum:
- 0
- 1
description: Enable (1) or disable (0) the SMTP check. SMTP verification is active by default. Turning it off may speed up responses but disables the `smtp_check` verdict.
example: 1
access_key:
name: access_key
in: query
required: true
schema:
type: string
description: Mailboxlayer API Access Key (required for all requests).
example: YOUR_ACCESS_KEY
email:
name: email
in: query
required: true
schema:
type: string
format: email
description: Email address to validate (single validation).
example: support@mailboxlayer.com
callback:
name: callback
in: query
required: false
schema:
type: string
description: JSONP callback function name; wrapper will be returned if specified.
example: myCallback
catch_all:
name: catch_all
in: query
required: false
schema:
type: integer
enum:
- 0
- 1
description: Enable catch-all mailbox detection by setting `catch_all=1`. Disabled by default because check is heavier and may increase response time. If not requested, the `catch_all` response value will typically be `null`. Some plans restrict catch-all detection.
example: 0
responses:
RateLimitReached:
description: Too Many Requests
content:
application/json:
schema:
$ref: '#/components/schemas/ApiError'
examples:
usage_limit_reached:
summary: usage_limit_reached
value:
success: false
error:
code: 104
type: usage_limit_reached
info: Your monthly usage limit has been reached. Please upgrade your Subscription Plan.
daily_usage_limit_reached:
summary: daily_usage_limit_reached
value:
success: false
error:
code: 104
type: daily_usage_limit_reached
info: Your daily usage limit has been reached. Please try again tomorrow or upgrade your subscription plan.
fair_use_limit_reached:
summary: fair_use_limit_reached
value:
success: false
error:
code: 104
type: fair_use_limit_reached
info: 'Your fair use limit has been reached. [Please contact support: support@apilayer.com]'
rate_limit_reached:
summary: rate_limit_reached
value:
success: false
error:
code: 106
type: rate_limit_reached
info: 'You have exceeded the maximum rate limitation allowed on your subscription plan. Please refer to the "Rate Limits" section of the API Documentation for details. '
InternalError:
description: Internal Server Error
content:
application/json:
schema:
$ref: '#/components/schemas/ApiError'
examples:
internal_error:
summary: internal_error
value:
success: false
error:
code: 0
type: internal_error
info: 'An error has occured. [Technical Support: support@apilayer.com]'
NotFound:
description: Not Found
content:
application/json:
schema:
$ref: '#/components/schemas/ApiError'
examples:
invalid_api_function:
summary: invalid_api_function
value:
success: false
error:
code: 103
type: invalid_api_function
info: This API Function does not exist.
404_not_found:
summary: 404_not_found
value:
success: false
error:
code: 404
type: 404_not_found
info: 404 - The requested resource could not be found. Please try again or contact support.
ValidationError:
description: Request-validation error — a required query parameter is missing or malformed (for example no `email` supplied). Returned with HTTP 422 and FastAPI's validation body.
content:
application/json:
schema:
$ref: '#/components/schemas/RequestValidationError'
examples:
missing_email:
value:
detail:
- loc:
- query
- email
msg: field required
type: value_error.missing
Unauthorized:
description: Unauthorized
content:
application/json:
schema:
$ref: '#/components/schemas/ApiError'
examples:
account_on_hold:
summary: account_on_hold
value:
success: false
error:
code: 107
type: account_on_hold
info: 'Your account currently has open invoices and API has been automatically disabled. Please settle your open balance or downgrade to the Free Plan to restore API access. [Support: support@apilayer.com]'
invalid_access_key:
summary: invalid_access_key
value:
success: false
error:
code: 101
type: invalid_access_key
info: 'You have not supplied a valid API Access Key. [Technical Support: support@apilayer.com]'
missing_access_key:
summary: missing_access_key
value:
success: false
error:
code: 101
type: missing_access_key
info: 'You have not supplied an API Access Key. [Required format: access_key=YOUR_ACCESS_KEY]'
inactive_user:
summary: inactive_user
value:
success: false
error:
code: 102
type: inactive_user
info: Permission denied - User not active.
Maintenance:
description: Service Unavailable
content:
application/json:
schema:
$ref: '#/components/schemas/ApiError'
examples:
maintenance_mode:
summary: maintenance_mode
value:
success: false
error:
code: 503
type: maintenance_mode
info: ''
Forbidden:
description: Forbidden
content:
application/json:
schema:
$ref: '#/components/schemas/ApiError'
examples:
https_access_restricted:
summary: https_access_restricted
value:
success: false
error:
code: 105
type: https_access_restricted
info: Access Restricted - Your current Subscription Plan does not support HTTPS Encryption.
function_access_restricted:
summary: function_access_restricted
value:
success: false
error:
code: 105
type: function_access_restricted
info: Access Restricted - Your current Subscription Plan does not support this API Function.
api_access_blocked:
summary: api_access_blocked
value:
success: false
error:
code: 104
type: api_access_blocked
info: Your API access has been temporarily disabled. Please upgrade your Subscription Plan or contact support.
schemas:
ApiError:
type: object
description: Standard error payload returned by Mailboxlayer when a request fails.
properties:
success:
type: boolean
description: Always false for error responses.
example: false
error:
type: object
properties:
code:
type: integer
description: Numeric error code as defined in Mailboxlayer docs.
example: 210
type:
type: string
description: Short machine-readable error type.
example: no_email_address_supplied
info:
type: string
description: Human-readable info / suggestion for correcting the request.
example: 'Please specify an email address. [Example: support@mailboxlayer.com]'
required:
- code
- type
- info
required:
- success
- error
EmailValidationResponse:
type: object
description: A single email validation result object. Fields may be `true`/`false` or `null` depending on whether a check was performed or supported by your plan.
properties:
email:
type: string
format: email
description: Exact email address as checked.
example: support@mailboxlayer.com
did_you_mean:
type:
- string
- 'null'
description: Suggested correction if a domain-typo is detected; empty string if none.
example: ''
user:
type:
- string
- 'null'
description: Local part (before the @) of the email address.
example: support
domain:
type:
- string
- 'null'
description: Domain part (after the @) of the email address.
example: mailboxlayer.com
format_valid:
type:
- boolean
- 'null'
description: Returns true if the email address syntax is valid per RFC rules.
example: true
mx_found:
type:
- boolean
- 'null'
description: True if MX records for the domain were found.
example: true
smtp_check:
type:
- boolean
- 'null'
description: Result of SMTP verification (true = mailbox appears to exist).
example: true
catch_all:
type:
- boolean
- 'null'
description: True if the domain accepts all emails (catch-all). If catch-all detection was not requested or not permitted on plan, this value may be null.
example: false
role:
type:
- boolean
- 'null'
description: True if the email address is a role account (e.g., admin, support).
example: false
disposable:
type:
- boolean
- 'null'
description: True if the address belongs to a known disposable / temporary provider.
example: false
free:
type:
- boolean
- 'null'
description: True if the email uses a known free provider (e.g., gmail.com).
example: true
score:
type:
- number
- 'null'
format: double
description: Aggregate quality/deliverability score between 0 (worst) and 1 (best).
example: 0.92
required:
- email
RequestValidationError:
type: object
description: FastAPI request-validation error body. Returned with HTTP 422 when a required query parameter is missing or malformed. This is a different shape from the ApiError envelope used for service-level errors (which are returned with HTTP 200).
properties:
detail:
type: array
items:
type: object
properties:
loc:
type: array
items:
type: string
example:
- query
- email
msg:
type: string
example: field required
type:
type: string
example: value_error.missing
securitySchemes:
AccessKeyQuery:
type: apiKey
in: query
name: access_key
description: Your Mailboxlayer API access key; pass as `access_key` query parameter.
externalDocs:
description: Official Mailboxlayer documentation (reference)
url: https://mailboxlayer.com/documentation