Ship Your First API Request

Overview

This quickstart walks through the minimum path from a developer account to a successful rates response. Use sandbox credentials when available.

1. 1

   Create a developer account

   Sign up for SyncShip and open the developer settings for your workspace.

2. 2

   Generate an API key

   Create a sandbox or production key and store it securely. Never commit keys to source control.

3. 3

   Shop rates

   Call POST /api/v1/shipments/rates with origin, destination, and weight.

4. 4

   Purchase a label

   Use POST /api/v1/shipments with an order id and the service you selected from rates.

Authentication

Pass your API key as a Bearer token on every request.

Authorization: Bearer YOUR_API_KEY

First endpoint

Start with the Rates API. Once quotes return, continue to Labels to purchase.

curl -X POST https://api.sync-ship.com/api/v1/shipments/rates \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{ "fromPostalCode": "10001", "toPostalCode": "90210", "toCountry": "US", "weightLb": 1, "weightOz": 0}'

First request

A minimal rates body needs origin ZIP, destination ZIP, and weight.

{
  "fromPostalCode": "10001",
  "toPostalCode": "90210",
  "toCountry": "US",
  "weightLb": 1,
  "weightOz": 0
}

Example response

You should receive a rates array. Amounts and services depend on enabled carriers and destination.

Example response

{
  "source": "estimated",
  "carriersAvailable": 1,
  "carriersTotal": 1,
  "rates": [
    {
      "carrier": "usps",
      "serviceCode": "priority",
      "serviceName": "Priority Mail",
      "amount": 8.5,
      "currency": "USD"
    }
  ]
}

Errors

Fix validation errors before retrying. Use backoff for rate limits.

• 401Missing or invalid API key.
• 422Validation failed — check postal codes or weight.
• 429Too many requests — retry with exponential backoff.

Next steps

Explore full Rates and Labels docs, then wire webhooks for downstream updates.