At a glance
Every request is an HTTPS call to a/v3 endpoint and includes your API key in the Authorization header. This example returns information about the authenticated user and confirms that your credentials work:
- Base URL:
https://api.reply.io, with all endpoints under the/v3prefix (for example,/v3/sequences). - Authentication: Bearer token in the
Authorizationheader on every request. - Format: JSON request and response bodies. Errors use
application/problem+json. - Rate limits: 100 requests per minute and 3,000 requests per hour, per user.
What you can do
The API covers every major area of the platform. Each area has its own group of endpoints in the API reference.| Area | What you can manage |
|---|---|
| Contacts & data | Contacts, contact lists, custom fields, and blacklist rules |
| Sequences | Multichannel sequences across email, LinkedIn, calls, and manual tasks |
| Accounts & templates | Connected email and LinkedIn accounts, plus shared templates |
| Inbox | Replies handled through the unified Inbox |
| Scheduling | Sending schedules and holiday calendars that control send times |
| Tasks | Manual tasks assigned to your team |
| Reporting | Performance reports across all channels |
| Automation | Webhooks for real-time events and background jobs for long-running operations |
API conventions
The API follows consistent patterns across endpoints.REST
Resource URLs use plural nouns and standard HTTP methods:GETto readPOSTto createPATCHto updateDELETEto remove
Errors
All4xx and 5xx responses use application/problem+json.
Business errors include a stable code in <resource>.<variant> format, so you can handle them programmatically:
400 Bad Request) also include an errors[] array. Each entry identifies the invalid field using a JSON Pointer.
Asynchronous jobs
Long-running operations, such as email validation and large bulk imports, return202 Accepted with a Location header that points to /v3/background-jobs/{id}.
Use the Background Jobs endpoint to check job status or cancel a job.
Authentication
v3 uses Bearer token authentication. Every request must include anAuthorization: Bearer <YOUR_API_KEY> header.
If the token is missing, invalid, or revoked, the API returns 401 Unauthorized with a WWW-Authenticate: Bearer header and an empty response body.
See Authentication for instructions on generating an API key, making your first authenticated request, using Master and Organization keys, and verifying credentials with /v3/whoami.
Rate limits
To protect the platform, requests are limited to 100 per minute and 3,000 per hour, per user. When you exceed a limit, the API returns429 Too Many Requests and includes a Retry-After header that tells you when to retry.
Reporting and statistics endpoints have stricter limits. See Rate Limits for details.
Versioning
v3 is the current supported version and should be used for all new integrations. API v1 and v2 remain available but are no longer supported and will be deprecated in the future. Their documentation is available atapidocs.reply.io.
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Authentication
Get an API key and make your first authenticated request.