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[canonical-links]
https://resend.com/docs/api-reference/introduction

[document-links]
/docs/llms.txt: /docs/llms.txt
API Key: https://resend.com/api-keys
API Reference: /docs/api-reference/introduction
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
Error 1010: /docs/knowledge-base/403-error-1010
Error Codes: /docs/api-reference/errors
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
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 Next: /docs/api-reference/pagination
Pagination: /docs/api-reference/pagination
Resend API vs SDK: /docs/api-vs-sdk
Resend CLI: /docs/cli
Resend SDKs: /docs/sdks
Resend home page: https://resend.com
Settings Usage page: https://resend.com/settings/usage
Sign In: https://resend.com/login
Usage Limits: /docs/api-reference/rate-limit
github: https://github.com/resend
official Resend SDK: /docs/sdks
pagination guide: /docs/api-reference/pagination
rate limits: /docs/api-reference/rate-limit
website: https://resend.com/
x: https://x.com/resend
youtube: https://www.youtube.com/@resendlabs

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[content]
Introduction - 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
Introduction
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
Base URL
Authentication
User-Agent
Response codes
Rate limit
FAQ
API Reference
Introduction
Copy page
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Understand general concepts, response codes, and authentication strategies.
Copy page
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For most use cases, we recommend using an
official Resend SDK
instead of calling the API directly. The SDKs handle authentication, required headers, and error handling for you. See
Resend API vs SDK
to decide which fits your project.
​
Base URL
The Resend API is built on
REST
principles.
HTTPS
is enforced in every request to improve data security, integrity, and privacy. The API does not support
HTTP
.
All requests contain the following base URL:
https://api.resend.com
​
Authentication
To authenticate you need to add an
Authorization
header with the contents of the header being
Bearer re_xxxxxxxxx
where
re_xxxxxxxxx
is your
API Key
.
Authorization: Bearer re_xxxxxxxxx
​
User-Agent
All API requests must include a
User-Agent
header. Requests without this header will be rejected with a
403
status code. Most HTTP clients, all
Resend SDKs
, and the
Resend CLI
include this header automatically, but if you’re making direct HTTP requests, make sure to set it:
User-Agent: my-app/1.0
If you’re getting a
403
error with error code
1010
despite having a valid API key, a missing
User-Agent
header is likely the cause. See
Error 1010
for more details.
​
Response codes
Resend uses standard HTTP codes to indicate the success or failure of your requests.
In general,
2xx
HTTP codes correspond to success,
4xx
codes are for user-related failures, and
5xx
codes are for infrastructure issues.
Status
Description
200
Successful request.
400
Check that the parameters were correct.
401
The API key used was missing.
403
The API key used was invalid.
404
The resource was not found.
429
The rate limit was exceeded.
5xx
Indicates an error with Resend servers.
Check
Error Codes
for a comprehensive breakdown of all possible API errors.
​
Rate limit
The default maximum rate limit is
10 requests per second per team
. This limit applies across all API keys associated with your team. This number can be increased for trusted senders by request. You can view your team’s current rate limit on the
Settings Usage page
. After that, you’ll hit the rate limit and receive a
429
response error code.
Learn more about our
rate limits
.
​
FAQ
How does pagination work with the API?
Some endpoints support cursor-based pagination to help you browse through large datasets efficiently. Check our
pagination guide
for detailed information on how to use pagination parameters.
How do you handle API versioning?
Currently, there’s no versioning system in place. We plan to add versioning via calendar-based headers in the future.
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