API Overview

The FlexOps API is a RESTful JSON API that gives you access to multi-carrier shipping, tracking, and analytics through a single integration.

Base URL

Environment	URL
Production	https://api.flexops.io/v1
Sandbox	https://sandbox.flexops.io/v1

tip

Use the sandbox environment for development and testing. All endpoints behave identically, but no real shipments are created and no charges are incurred.

Authentication

All requests require an API key via the X-API-Key header:

curl -X GET https://api.flexops.io/v1/carriers \
  -H "X-API-Key: your-api-key"

See Authentication for details on API keys and JWT bearer tokens.

Request flow

A typical shipping integration follows this pattern:

Request format

All request bodies must be JSON with Content-Type: application/json.

Response format

All responses return JSON. Successful responses return the resource directly:

{
  "id": "lbl_abc123",
  "trackingNumber": "9400111899223456789012",
  "carrier": "usps",
  "service": "priority",
  "status": "created",
  "labelUrl": "https://api.flexops.io/v1/labels/lbl_abc123/download",
  "rate": {
    "amount": 7.85,
    "currency": "USD"
  },
  "createdAt": "2026-03-10T14:30:00Z"
}

List endpoints return paginated results:

{
  "data": [...],
  "pagination": {
    "page": 1,
    "pageSize": 25,
    "totalCount": 142,
    "totalPages": 6
  }
}

Idempotency

All POST requests support idempotency via the Idempotency-Key header:

curl -X POST https://api.flexops.io/v1/labels \
  -H "X-API-Key: your-api-key" \
  -H "Idempotency-Key: order-12345-label" \
  -H "Content-Type: application/json" \
  -d '{...}'

If you retry the same request with the same idempotency key, you'll receive the original response without creating a duplicate resource. Keys expire after 24 hours.

warning

The idempotency key is scoped to your workspace. If you send the same key with a different request body, the API returns a 409 Conflict error.

Correlation IDs

Every response includes an X-Correlation-ID header. Include this when contacting support for faster issue resolution.

Endpoints at a glance

Endpoint	Methods	Description
/v1/shipments	POST, GET	Create and list shipments
/v1/rates	POST	Compare carrier rates
/v1/tracking/:number	GET	Track shipments
/v1/labels	POST, GET	Create, retrieve, and download labels
/v1/addresses/validate	POST	Validate and standardize addresses
/v1/carriers	GET	List carriers and services
/v1/webhooks	POST, GET, DELETE	Manage webhook subscriptions
/v1/analytics	GET, POST	Savings, performance, and predictions