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og:title: Errors - Resend
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[canonical-links]
https://resend.com/docs/api-reference/errors

[document-links]
/docs/llms.txt: /docs/llms.txt
API Reference: /docs/api-reference/introduction
API key in the dashboard: https://resend.com/api-keys
Contact support: https://resend.com/contact
DEL Delete API key: /docs/api-reference/api-keys/delete-api-key
DEL Delete Audience: /docs/api-reference/audiences/delete-audience
DEL Delete Automation: /docs/api-reference/automations/delete-automation
DEL Delete Broadcast: /docs/api-reference/broadcasts/delete-broadcast
DEL Delete Contact Property: /docs/api-reference/contact-properties/delete-contact-property
DEL Delete Contact Segment: /docs/api-reference/contacts/delete-contact-segment
DEL Delete Contact: /docs/api-reference/contacts/delete-contact
DEL Delete Domain: /docs/api-reference/domains/delete-domain
DEL Delete Event: /docs/api-reference/events/delete-event
DEL Delete Segment: /docs/api-reference/segments/delete-segment
DEL Delete Template: /docs/api-reference/templates/delete-template
DEL Delete Topic: /docs/api-reference/topics/delete-topic
DEL Delete Webhook: /docs/api-reference/webhooks/delete-webhook
DEL Remove Suppression: /docs/api-reference/suppressions/remove-suppression
DEL Revoke Grant: /docs/api-reference/oauth/revoke-grant
Documentation: /docs/introduction
Errors: /docs/api-reference/errors
GET Authorize: /docs/api-reference/oauth/authorize
GET Get Domain Claim: /docs/api-reference/domains/get-domain-claim
GET Get Template: /docs/api-reference/templates/get-template
GET List API keys: /docs/api-reference/api-keys/list-api-keys
GET List Attachments: /docs/api-reference/emails/list-email-attachments
GET List Attachments: /docs/api-reference/emails/list-received-email-attachments
GET List Attempts BETA: /docs/api-reference/webhooks/list-event-attempts
GET List Audiences: /docs/api-reference/audiences/list-audiences
GET List Automation Runs: /docs/api-reference/automations/list-automation-runs
GET List Automations: /docs/api-reference/automations/list-automations
GET List Broadcasts: /docs/api-reference/broadcasts/list-broadcasts
GET List Contact Imports: /docs/api-reference/contacts/list-contact-imports
GET List Contact Properties: /docs/api-reference/contact-properties/list-contact-properties
GET List Contact Segments: /docs/api-reference/contacts/list-contact-segments
GET List Contacts: /docs/api-reference/contacts/list-contacts
GET List Domains: /docs/api-reference/domains/list-domains
GET List Events BETA: /docs/api-reference/webhooks/list-events
GET List Events: /docs/api-reference/events/list-events
GET List Grants: /docs/api-reference/oauth/list-grants
GET List Logs: /docs/api-reference/logs/list-logs
GET List Received Emails: /docs/api-reference/emails/list-received-emails
GET List Recipients BETA: /docs/api-reference/broadcasts/list-broadcast-recipients
GET List Segment Contacts: /docs/api-reference/segments/list-segment-contacts
GET List Segments: /docs/api-reference/segments/list-segments
GET List Sent Emails: /docs/api-reference/emails/list-emails
GET List Suppressions: /docs/api-reference/suppressions/list-suppressions
GET List Templates: /docs/api-reference/templates/list-templates
GET List Topics: /docs/api-reference/topics/list-topics
GET List Webhooks: /docs/api-reference/webhooks/list-webhooks
GET Retrieve Attachment: /docs/api-reference/emails/retrieve-email-attachment
GET Retrieve Attachment: /docs/api-reference/emails/retrieve-received-email-attachment
GET Retrieve Audience: /docs/api-reference/audiences/get-audience
GET Retrieve Automation Run: /docs/api-reference/automations/get-automation-run
GET Retrieve Automation: /docs/api-reference/automations/get-automation
GET Retrieve Broadcast: /docs/api-reference/broadcasts/get-broadcast
GET Retrieve Contact Import: /docs/api-reference/contacts/get-contact-import
GET Retrieve Contact Property: /docs/api-reference/contact-properties/get-contact-property
GET Retrieve Contact Topics: /docs/api-reference/contacts/get-contact-topics
GET Retrieve Contact: /docs/api-reference/contacts/get-contact
GET Retrieve Domain: /docs/api-reference/domains/get-domain
GET Retrieve Event BETA: /docs/api-reference/webhooks/get-event
GET Retrieve Event: /docs/api-reference/events/get-event
GET Retrieve Log: /docs/api-reference/logs/retrieve-log
GET Retrieve Metrics BETA: /docs/api-reference/broadcasts/get-broadcast-metrics
GET Retrieve Metrics BETA: /docs/api-reference/emails/get-metrics
GET Retrieve Metrics BETA: /docs/api-reference/segments/get-segment-metrics
GET Retrieve Received Email: /docs/api-reference/emails/retrieve-received-email
GET Retrieve Segment: /docs/api-reference/segments/get-segment
GET Retrieve Sent Email: /docs/api-reference/emails/retrieve-email
GET Retrieve Suppression: /docs/api-reference/suppressions/get-suppression
GET Retrieve Topic: /docs/api-reference/topics/get-topic
GET Retrieve Usage: /docs/api-reference/usage/retrieve-usage
GET Retrieve Webhook: /docs/api-reference/webhooks/get-webhook
Get Started: https://resend.com/signup
Guides: /docs/knowledge-base/introduction
Introduction: /docs/api-reference/introduction
Learn more about resolving this error: /docs/knowledge-base/403-error-domain-mismatch
Learn more about resolving this error: /docs/knowledge-base/403-error-resend-dev-domain
Learn more about resolving this error: /docs/knowledge-base/domain-already-registered
PATCH Update Automation: /docs/api-reference/automations/update-automation
PATCH Update Broadcast: /docs/api-reference/broadcasts/update-broadcast
PATCH Update Contact Property: /docs/api-reference/contact-properties/update-contact-property
PATCH Update Contact Topics: /docs/api-reference/contacts/update-contact-topics
PATCH Update Contact: /docs/api-reference/contacts/update-contact
PATCH Update Domain: /docs/api-reference/domains/update-domain
PATCH Update Email: /docs/api-reference/emails/update-email
PATCH Update Event: /docs/api-reference/events/update-event
PATCH Update Template: /docs/api-reference/templates/update-template
PATCH Update Topic: /docs/api-reference/topics/update-topic
PATCH Update Webhook: /docs/api-reference/webhooks/update-webhook
POST Add Batch Suppressions: /docs/api-reference/suppressions/add-batch-suppressions
POST Add Contact to Segment: /docs/api-reference/contacts/add-contact-to-segment
POST Add Suppression: /docs/api-reference/suppressions/add-suppression
POST Cancel Email: /docs/api-reference/emails/cancel-email
POST Claim Domain: /docs/api-reference/domains/claim-domain
POST Create API key: /docs/api-reference/api-keys/create-api-key
POST Create Audience: /docs/api-reference/audiences/create-audience
POST Create Automation: /docs/api-reference/automations/create-automation
POST Create Broadcast: /docs/api-reference/broadcasts/create-broadcast
POST Create Contact Import: /docs/api-reference/contacts/create-contact-import
POST Create Contact Property: /docs/api-reference/contact-properties/create-contact-property
POST Create Contact: /docs/api-reference/contacts/create-contact
POST Create Domain: /docs/api-reference/domains/create-domain
POST Create Event: /docs/api-reference/events/create-event
POST Create Segment: /docs/api-reference/segments/create-segment
POST Create Template: /docs/api-reference/templates/create-template
POST Create Topic: /docs/api-reference/topics/create-topic
POST Create Webhook: /docs/api-reference/webhooks/create-webhook
POST Duplicate Template: /docs/api-reference/templates/duplicate-template
POST Publish Template: /docs/api-reference/templates/publish-template
POST Register Client: /docs/api-reference/oauth/register
POST Remove Batch Suppressions: /docs/api-reference/suppressions/remove-batch-suppressions
POST Revoke Token: /docs/api-reference/oauth/revoke
POST Send Batch Emails: /docs/api-reference/emails/send-batch-emails
POST Send Broadcast: /docs/api-reference/broadcasts/send-broadcast
POST Send Email: /docs/api-reference/emails/send-email
POST Send Event: /docs/api-reference/events/send-event
POST Stop Automation: /docs/api-reference/automations/stop-automation
POST Token: /docs/api-reference/oauth/token
POST Verify Domain Claim: /docs/api-reference/domains/verify-domain-claim
POST Verify Domain: /docs/api-reference/domains/verify-domain
Pagination: /docs/api-reference/pagination
Resend home page: https://resend.com
Resend’s Domain page: https://resend.com/domains
Send Email Next: /docs/api-reference/emails/send-email
Sign In: https://resend.com/login
Upgrade your plan: https://resend.com/settings/billing
Usage Limits Previous: /docs/api-reference/rate-limit
Usage Limits: /docs/api-reference/rate-limit
contact support: https://resend.com/contact
contact support: https://resend.com/help
github: https://github.com/resend
response headers: /docs/api-reference/introduction#rate-limit
status page: https://resend-status.com
website: https://resend.com/
x: https://x.com/resend
youtube: https://www.youtube.com/@resendlabs

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[content]
Errors - Resend
Documentation Index
Fetch the complete documentation index at:
/docs/llms.txt
Use this file to discover all available pages before exploring further.
Skip to main content
Resend
home page
Documentation
Guides
API Reference
Sign In
Get Started
Get Started
Search...
Navigation
API Reference
Errors
Search...
⌘
K
API Reference
Introduction
Pagination
Usage Limits
Errors
Sending
POST
Send Email
POST
Send Batch Emails
GET
Retrieve Sent Email
GET
List Sent Emails
PATCH
Update Email
POST
Cancel Email
GET
Retrieve Attachment
GET
List Attachments
GET
Retrieve Metrics
BETA
Receiving
GET
Retrieve Received Email
GET
List Received Emails
GET
Retrieve Attachment
GET
List Attachments
Broadcasts
POST
Create Broadcast
POST
Send Broadcast
GET
Retrieve Broadcast
GET
List Broadcasts
PATCH
Update Broadcast
DEL
Delete Broadcast
GET
Retrieve Metrics
BETA
GET
List Recipients
BETA
Automations
POST
Create Automation
PATCH
Update Automation
GET
Retrieve Automation
GET
List Automations
POST
Stop Automation
DEL
Delete Automation
GET
List Automation Runs
GET
Retrieve Automation Run
Events
POST
Create Event
POST
Send Event
GET
Retrieve Event
GET
List Events
PATCH
Update Event
DEL
Delete Event
Templates
POST
Create Template
GET
Get Template
GET
List Templates
PATCH
Update Template
DEL
Delete Template
POST
Publish Template
POST
Duplicate Template
Contacts
POST
Create Contact
GET
Retrieve Contact
GET
List Contacts
PATCH
Update Contact
DEL
Delete Contact
POST
Add Contact to Segment
GET
List Contact Segments
DEL
Delete Contact Segment
GET
Retrieve Contact Topics
PATCH
Update Contact Topics
Contact Properties
POST
Create Contact Property
GET
Retrieve Contact Property
GET
List Contact Properties
PATCH
Update Contact Property
DEL
Delete Contact Property
Contact Imports
POST
Create Contact Import
GET
Retrieve Contact Import
GET
List Contact Imports
Segments
POST
Create Segment
GET
Retrieve Segment
GET
List Segments
DEL
Delete Segment
GET
List Segment Contacts
GET
Retrieve Metrics
BETA
Topics
POST
Create Topic
GET
Retrieve Topic
GET
List Topics
PATCH
Update Topic
DEL
Delete Topic
Audiences
DEPRECATED
POST
Create Audience
GET
Retrieve Audience
GET
List Audiences
DEL
Delete Audience
Domains
POST
Create Domain
POST
Claim Domain
GET
Get Domain Claim
POST
Verify Domain Claim
POST
Verify Domain
GET
Retrieve Domain
GET
List Domains
PATCH
Update Domain
DEL
Delete Domain
Logs
GET
Retrieve Log
GET
List Logs
Usage
BETA
GET
Retrieve Usage
API Keys
POST
Create API key
GET
List API keys
DEL
Delete API key
Suppressions
POST
Add Suppression
GET
Retrieve Suppression
GET
List Suppressions
DEL
Remove Suppression
POST
Add Batch Suppressions
POST
Remove Batch Suppressions
Authorized Apps
GET
List Grants
DEL
Revoke Grant
Webhooks
POST
Create Webhook
GET
Retrieve Webhook
GET
List Webhooks
PATCH
Update Webhook
DEL
Delete Webhook
GET
List Events
BETA
GET
Retrieve Event
BETA
GET
List Attempts
BETA
OAuth
POST
Register Client
GET
Authorize
POST
Token
POST
Revoke Token
On this page
Error schema
invalid_idempotency_key
validation_error
missing_api_key
restricted_api_key
invalid_api_key
validation_error
validation_error
validation_error
not_found
method_not_allowed
invalid_idempotent_request
concurrent_idempotent_requests
invalid_attachment
invalid_from_address
invalid_access
invalid_parameter
invalid_region
missing_required_field
monthly_quota_exceeded
daily_quota_exceeded
rate_limit_exceeded
security_error
application_error
internal_server_error
API Reference
Errors
Copy page
Copy page
Troubleshoot problems with this comprehensive breakdown of all error codes.
Copy page
Copy page
​
Error schema
Resend uses standard HTTP response codes for success and failure notifications, and errors are further classified by type.
​
invalid_idempotency_key
Status:
400
Message:
The key must be between 1–256 chars.
Suggested action:
Retry with a valid idempotency key.
​
validation_error
Status:
400
Message:
An error was found with one or more fields in the request.
Suggested action:
The message will contain more details about what field and error were found.
​
missing_api_key
Status:
401
Message:
Missing API key in the authorization header.
Suggested action:
Include the following header in the request:
Authorization: Bearer YOUR_API_KEY
.
​
restricted_api_key
Status:
401
Message:
This API key is restricted to only send emails.
Suggested action:
Make sure the API key has
Full access
to perform actions other than sending emails.
​
invalid_api_key
Status:
403
Message:
API key is invalid.
Suggested action:
Make sure the API key is correct or generate a new
API key in the dashboard
.
​
validation_error
Status:
403
Message:
You can only send testing emails to your own email address (
youremail@domain.com
). To send emails to other recipients, please verify a domain at resend.com/domains, and change the
from
address to an email using this domain.
Suggested action:
In
Resend’s Domain page
, add and verify a domain for which you have DNS access. This allows you to send emails to addresses beyond your own.
Learn more about resolving this error
.
​
validation_error
Status:
403
Message:
The
domain.com
domain is not verified. Please, add and verify your domain.
Suggested action:
Make sure the domain in your API request’s
from
field matches a domain you’ve verified in Resend. Update your API request to use your verified domain, or add and verify the domain you’re trying to use.
Learn more about resolving this error
.
​
validation_error
Status:
403
Message:
The
example.com
domain has been registered already.
Suggested action:
Verify you are signed in to the correct Resend account and check whether a teammate already added the domain. If you still cannot access it,
contact support
.
Learn more about resolving this error
.
​
not_found
Status:
404
Message:
The requested endpoint does not exist.
Suggested action:
Change your request URL to match a valid API endpoint.
​
method_not_allowed
Status:
405
Message:
Method is not allowed for the requested path.
Suggested action:
Change your API endpoint to use a valid method.
​
invalid_idempotent_request
Status:
409
Message:
Same idempotency key used with a different request payload.
Suggested action:
Change your idempotency key or payload.
​
concurrent_idempotent_requests
Status:
409
Message:
Same idempotency key used while original request is still in progress.
Suggested action:
Try the request again later.
​
invalid_attachment
Status:
422
Message:
Attachment must have either a
content
or
path
.
Suggested action:
Attachments must either have a
content
(strings, Buffer, or Stream contents) or
path
to a remote resource (better for larger attachments).
​
invalid_from_address
Status:
422
Message:
Invalid
from
field.
Suggested action:
Make sure the
from
field is valid. The email address needs to follow the
email@example.com
or
Name <email@example.com>
format.
​
invalid_access
Status:
422
Message:
Access must be “full_access” | “sending_access”.
Suggested action:
Make sure the API key has necessary permissions.
​
invalid_parameter
Status:
422
Message:
The
parameter
must be a valid UUID.
Suggested action:
Check the value and make sure it’s valid.
​
invalid_region
Status:
422
Message:
Region must be “us-east-1” | “eu-west-1” | “sa-east-1”.
Suggested action:
Make sure the correct region is selected.
​
missing_required_field
Status:
422
Message:
The request body is missing one or more required fields.
Suggested action:
Check the error message to see the list of missing fields.
​
monthly_quota_exceeded
Status:
429
Message:
You have reached your monthly email quota.
Suggested action:
Upgrade your plan
to increase the monthly email quota. Both sent and received emails count towards this quota.
​
daily_quota_exceeded
Status:
429
Message:
You have reached your daily email quota.
Suggested action:
Upgrade your plan
to remove the daily quota limit or wait until 24 hours have passed. Both sent and received emails count towards this quota.
​
rate_limit_exceeded
Status:
429
Message:
Too many requests. Please limit the number of requests per second. Or
contact support
to increase rate limit.
Suggested action:
Read the
response headers
and reduce the rate at which you request the API. This can be done by introducing a queue mechanism or reducing the number of concurrent requests per second. If you have specific requirements,
contact support
to request a rate increase.
​
security_error
Status:
451
Message:
A possible security issue was found with the request.
Suggested action:
The message will contain more details.
Contact support
for more information.
​
application_error
Status:
500
Message:
An unexpected error occurred.
Suggested action:
Try the request again later. If the error does not resolve, check our
status page
for service updates.
​
internal_server_error
Status:
500
Message:
An unexpected error occurred.
Suggested action:
Try the request again later. If the error does not resolve, check our
status page
for service updates.
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