Create Shipment Label

Creates a shipping label. The labelData field returned in the response is a base64 encoded PDF value. Yopu can decode and save the output as a PDF file to retrieve a printable label. The body of this request has the following attributes:

Name	Data Type	Description
`carrierCode`	string	Identifies the carrier to be used for this label. Required
`serviceCode`	string	Identifies the shipping service to be used for this label. Required
`packageCode`	string	Identifies the packing type that should be used for this label. Required
`confirmation`	string	The type of delivery confirmation that is to be used once the shipment is created. Possible values: `none`, `delivery`, `signature`, `adult_signature`, and `direct_signature`. `direct_signature` is available for FedEx only. Optional
`shipDate`	string	The date the shipment will be shipped. Required
`weight`	Object: numbers and strings	Weight of the order. Required
`dimensions`	Object: numbers and strings	Dimensions of the order.
`shipFrom`	Address	Address indicating shipment's origin. Use the Address model. Required
`shipTo`	Address	Address indicating shipment's destination. Use the Address model. Required
`insuranceOptions`	Object: numbers, strings, and boolean	The shipping insurance information associated with this order. Learn more about InsuranceOptions
`internationalOptions`	Object: strings, and an Array of customs items	Customs information that can be used to generate customs documents for international orders. Learn more about InternationalOptions Optional
`advancedOptions`	Object: numbers, strings, and boolean	Various AdvancedOptions may be available depending on the shipping carrier that is used to ship the order. Optional
`testLabel`	boolean	Specifies whether a test label should be created. Default value: false. Optional

IMPORTANT

Active Manual Store Required

You must have at least one active Manual Store on your ShipStation account to create labels with this endpoint.

If you deactivated the Manual Store your ShipStation account initially came with, you must activate one. Otherwise, if you try to create labels with this endpoint, you will see a 500 error that reads, “Object reference not set to an instance of an object.”

Example Request

POST /shipments/createlabel HTTP/1.1
Host: ssapi.shipstation.com
Authorization: __YOUR_AUTH_HERE__
Content-Type: application/json

{
  "carrierCode": "fedex",
  "serviceCode": "fedex_ground",
  "packageCode": "package",
  "confirmation": "delivery",
  "shipDate": "2014-04-03",
  "weight": {
    "value": 3,
    "units": "ounces"
  },
  "dimensions": {
    "units": "inches",
    "length": 7,
    "width": 5,
    "height": 6
  },
  "shipFrom": {
    "name": "Jason Hodges",
    "company": "ShipStation",
    "street1": "2815 Exposition Blvd",
    "street2": "Ste 2353242",
    "street3": null,
    "city": "Austin",
    "state": "TX",
    "postalCode": "78703",
    "country": "US",
    "phone": null,
    "residential": false
  },
  "shipTo": {
    "name": "The President",
    "company": "US Govt",
    "street1": "1600 Pennsylvania Ave",
    "street2": "Oval Office",
    "street3": null,
    "city": "Washington",
    "state": "DC",
    "postalCode": "20500",
    "country": "US",
    "phone": null,
    "residential": false
  },
  "insuranceOptions": null,
  "internationalOptions": null,
  "advancedOptions": null,
  "testLabel": false
}

curl -iX POST https://ssapi.shipstation.com/shipments/createlabel \
-H 'Authorization: __YOUR_AUTH_HERE__' \
-H 'Content-Type: application/json' \
-d '{
  "carrierCode": "fedex",
  "serviceCode": "fedex_ground",
  "packageCode": "package",
  "confirmation": "delivery",
  "shipDate": "2014-04-03",
  "weight": {
    "value": 3,
    "units": "ounces"
  },
  "dimensions": {
    "units": "inches",
    "length": 7,
    "width": 5,
    "height": 6
  },
  "shipFrom": {
    "name": "Jason Hodges",
    "company": "ShipStation",
    "street1": "2815 Exposition Blvd",
    "street2": "Ste 2353242",
    "street3": null,
    "city": "Austin",
    "state": "TX",
    "postalCode": "78703",
    "country": "US",
    "phone": null,
    "residential": false
  },
  "shipTo": {
    "name": "The President",
    "company": "US Govt",
    "street1": "1600 Pennsylvania Ave",
    "street2": "Oval Office",
    "street3": null,
    "city": "Washington",
    "state": "DC",
    "postalCode": "20500",
    "country": "US",
    "phone": null,
    "residential": false
  },
  "insuranceOptions": null,
  "internationalOptions": null,
  "advancedOptions": null,
  "testLabel": false
}'

$headers = New-Object "System.Collections.Generic.Dictionary[[String],[String]]"
$headers.Add("Host", "ssapi.shipstation.com")
$headers.Add("Authorization", "__YOUR_AUTH_HERE__")
$headers.Add("Content-Type", "application/json")

$body = "{`n  `"carrierCode`": `"fedex`",`n  `"serviceCode`": `"fedex_ground`",`n  `"packageCode`": `"package`",`n  `"confirmation`": `"delivery`",`n  `"shipDate`": `"2014-04-03`",`n  `"weight`": {`n    `"value`": 3,`n    `"units`": `"ounces`"`n  },`n  `"dimensions`": {`n    `"units`": `"inches`",`n    `"length`": 7,`n    `"width`": 5,`n    `"height`": 6`n  },`n  `"shipFrom`": {`n    `"name`": `"Jason Hodges`",`n    `"company`": `"ShipStation`",`n    `"street1`": `"2815 Exposition Blvd`",`n    `"street2`": `"Ste 2353242`",`n    `"street3`": null,`n    `"city`": `"Austin`",`n    `"state`": `"TX`",`n    `"postalCode`": `"78703`",`n    `"country`": `"US`",`n    `"phone`": null,`n    `"residential`": false`n  },`n  `"shipTo`": {`n    `"name`": `"The President`",`n    `"company`": `"US Govt`",`n    `"street1`": `"1600 Pennsylvania Ave`",`n    `"street2`": `"Oval Office`",`n    `"street3`": null,`n    `"city`": `"Washington`",`n    `"state`": `"DC`",`n    `"postalCode`": `"20500`",`n    `"country`": `"US`",`n    `"phone`": null,`n    `"residential`": false`n  },`n  `"insuranceOptions`": null,`n  `"internationalOptions`": null,`n  `"advancedOptions`": null,`n  `"testLabel`": false`n}"

$response = Invoke-RestMethod 'https://ssapi.shipstation.com/shipments/createlabel' -Method 'POST' -Headers $headers -Body $body
$response | ConvertTo-Json

var myHeaders = new Headers();
myHeaders.append("Host", "ssapi.shipstation.com");
myHeaders.append("Authorization", "__YOUR_AUTH_HERE__");
myHeaders.append("Content-Type", "application/json");

var raw = JSON.stringify({"carrierCode":"fedex","serviceCode":"fedex_ground","packageCode":"package","confirmation":"delivery","shipDate":"2014-04-03","weight":{"value":3,"units":"ounces"},"dimensions":{"units":"inches","length":7,"width":5,"height":6},"shipFrom":{"name":"Jason Hodges","company":"ShipStation","street1":"2815 Exposition Blvd","street2":"Ste 2353242","street3":null,"city":"Austin","state":"TX","postalCode":"78703","country":"US","phone":null,"residential":false},"shipTo":{"name":"The President","company":"US Govt","street1":"1600 Pennsylvania Ave","street2":"Oval Office","street3":null,"city":"Washington","state":"DC","postalCode":"20500","country":"US","phone":null,"residential":false},"insuranceOptions":null,"internationalOptions":null,"advancedOptions":null,"testLabel":false});

var requestOptions = {
  method: 'POST',
  headers: myHeaders,
  body: raw,
  redirect: 'follow'
};

fetch("https://ssapi.shipstation.com/shipments/createlabel", requestOptions)
  .then(response => response.text())
  .then(result => console.log(result))
  .catch(error => console.log('error', error));

var request = require('request');
var options = {
  'method': 'POST',
  'url': 'https://ssapi.shipstation.com/shipments/createlabel',
  'headers': {
    'Host': 'ssapi.shipstation.com',
    'Authorization': '__YOUR_AUTH_HERE__',
    'Content-Type': 'application/json'
  },
  body: JSON.stringify({"carrierCode":"fedex","serviceCode":"fedex_ground","packageCode":"package","confirmation":"delivery","shipDate":"2014-04-03","weight":{"value":3,"units":"ounces"},"dimensions":{"units":"inches","length":7,"width":5,"height":6},"shipFrom":{"name":"Jason Hodges","company":"ShipStation","street1":"2815 Exposition Blvd","street2":"Ste 2353242","street3":null,"city":"Austin","state":"TX","postalCode":"78703","country":"US","phone":null,"residential":false},"shipTo":{"name":"The President","company":"US Govt","street1":"1600 Pennsylvania Ave","street2":"Oval Office","street3":null,"city":"Washington","state":"DC","postalCode":"20500","country":"US","phone":null,"residential":false},"insuranceOptions":null,"internationalOptions":null,"advancedOptions":null,"testLabel":false})

};
request(options, function (error, response) { 
  if (error) throw new Error(error);
  console.log(response.body);
});

<?php

$curl = curl_init();

curl_setopt_array($curl, array(
  CURLOPT_URL => "https://ssapi.shipstation.com/shipments/createlabel",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 0,
  CURLOPT_FOLLOWLOCATION => true,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "POST",
  CURLOPT_POSTFIELDS =>"{\n  \"carrierCode\": \"fedex\",\n  \"serviceCode\": \"fedex_ground\",\n  \"packageCode\": \"package\",\n  \"confirmation\": \"delivery\",\n  \"shipDate\": \"2014-04-03\",\n  \"weight\": {\n    \"value\": 3,\n    \"units\": \"ounces\"\n  },\n  \"dimensions\": {\n    \"units\": \"inches\",\n    \"length\": 7,\n    \"width\": 5,\n    \"height\": 6\n  },\n  \"shipFrom\": {\n    \"name\": \"Jason Hodges\",\n    \"company\": \"ShipStation\",\n    \"street1\": \"2815 Exposition Blvd\",\n    \"street2\": \"Ste 2353242\",\n    \"street3\": null,\n    \"city\": \"Austin\",\n    \"state\": \"TX\",\n    \"postalCode\": \"78703\",\n    \"country\": \"US\",\n    \"phone\": null,\n    \"residential\": false\n  },\n  \"shipTo\": {\n    \"name\": \"The President\",\n    \"company\": \"US Govt\",\n    \"street1\": \"1600 Pennsylvania Ave\",\n    \"street2\": \"Oval Office\",\n    \"street3\": null,\n    \"city\": \"Washington\",\n    \"state\": \"DC\",\n    \"postalCode\": \"20500\",\n    \"country\": \"US\",\n    \"phone\": null,\n    \"residential\": false\n  },\n  \"insuranceOptions\": null,\n  \"internationalOptions\": null,\n  \"advancedOptions\": null,\n  \"testLabel\": false\n}",
  CURLOPT_HTTPHEADER => array(
    "Host: ssapi.shipstation.com",
    "Authorization: __YOUR_AUTH_HERE__",
    "Content-Type: application/json"
  ),
));

$response = curl_exec($curl);

curl_close($curl);
echo $response;

import requests

url = "https://ssapi.shipstation.com/shipments/createlabel"

payload = "{\n  \"carrierCode\": \"fedex\",\n  \"serviceCode\": \"fedex_ground\",\n  \"packageCode\": \"package\",\n  \"confirmation\": \"delivery\",\n  \"shipDate\": \"2014-04-03\",\n  \"weight\": {\n    \"value\": 3,\n    \"units\": \"ounces\"\n  },\n  \"dimensions\": {\n    \"units\": \"inches\",\n    \"length\": 7,\n    \"width\": 5,\n    \"height\": 6\n  },\n  \"shipFrom\": {\n    \"name\": \"Jason Hodges\",\n    \"company\": \"ShipStation\",\n    \"street1\": \"2815 Exposition Blvd\",\n    \"street2\": \"Ste 2353242\",\n    \"street3\": null,\n    \"city\": \"Austin\",\n    \"state\": \"TX\",\n    \"postalCode\": \"78703\",\n    \"country\": \"US\",\n    \"phone\": null,\n    \"residential\": false\n  },\n  \"shipTo\": {\n    \"name\": \"The President\",\n    \"company\": \"US Govt\",\n    \"street1\": \"1600 Pennsylvania Ave\",\n    \"street2\": \"Oval Office\",\n    \"street3\": null,\n    \"city\": \"Washington\",\n    \"state\": \"DC\",\n    \"postalCode\": \"20500\",\n    \"country\": \"US\",\n    \"phone\": null,\n    \"residential\": false\n  },\n  \"insuranceOptions\": null,\n  \"internationalOptions\": null,\n  \"advancedOptions\": null,\n  \"testLabel\": false\n}"
headers = {
  'Host': 'ssapi.shipstation.com',
  'Authorization': '__YOUR_AUTH_HERE__',
  'Content-Type': 'application/json'
}

response = requests.request("POST", url, headers=headers, data = payload)

print(response.text.encode('utf8'))

require "uri"
require "net/http"

url = URI("https://ssapi.shipstation.com/shipments/createlabel")

https = Net::HTTP.new(url.host, url.port);
https.use_ssl = true

request = Net::HTTP::Post.new(url)
request["Host"] = "ssapi.shipstation.com"
request["Authorization"] = "__YOUR_AUTH_HERE__"
request["Content-Type"] = "application/json"
request.body = "{\n  \"carrierCode\": \"fedex\",\n  \"serviceCode\": \"fedex_ground\",\n  \"packageCode\": \"package\",\n  \"confirmation\": \"delivery\",\n  \"shipDate\": \"2014-04-03\",\n  \"weight\": {\n    \"value\": 3,\n    \"units\": \"ounces\"\n  },\n  \"dimensions\": {\n    \"units\": \"inches\",\n    \"length\": 7,\n    \"width\": 5,\n    \"height\": 6\n  },\n  \"shipFrom\": {\n    \"name\": \"Jason Hodges\",\n    \"company\": \"ShipStation\",\n    \"street1\": \"2815 Exposition Blvd\",\n    \"street2\": \"Ste 2353242\",\n    \"street3\": null,\n    \"city\": \"Austin\",\n    \"state\": \"TX\",\n    \"postalCode\": \"78703\",\n    \"country\": \"US\",\n    \"phone\": null,\n    \"residential\": false\n  },\n  \"shipTo\": {\n    \"name\": \"The President\",\n    \"company\": \"US Govt\",\n    \"street1\": \"1600 Pennsylvania Ave\",\n    \"street2\": \"Oval Office\",\n    \"street3\": null,\n    \"city\": \"Washington\",\n    \"state\": \"DC\",\n    \"postalCode\": \"20500\",\n    \"country\": \"US\",\n    \"phone\": null,\n    \"residential\": false\n  },\n  \"insuranceOptions\": null,\n  \"internationalOptions\": null,\n  \"advancedOptions\": null,\n  \"testLabel\": false\n}"

response = https.request(request)
puts response.read_body

var client = new RestClient("https://ssapi.shipstation.com/shipments/createlabel");
client.Timeout = -1;
var request = new RestRequest(Method.POST);
request.AddHeader("Host", "ssapi.shipstation.com");
request.AddHeader("Authorization", "__YOUR_AUTH_HERE__");
request.AddHeader("Content-Type", "application/json");
request.AddParameter("application/json", "{\n  \"carrierCode\": \"fedex\",\n  \"serviceCode\": \"fedex_ground\",\n  \"packageCode\": \"package\",\n  \"confirmation\": \"delivery\",\n  \"shipDate\": \"2014-04-03\",\n  \"weight\": {\n    \"value\": 3,\n    \"units\": \"ounces\"\n  },\n  \"dimensions\": {\n    \"units\": \"inches\",\n    \"length\": 7,\n    \"width\": 5,\n    \"height\": 6\n  },\n  \"shipFrom\": {\n    \"name\": \"Jason Hodges\",\n    \"company\": \"ShipStation\",\n    \"street1\": \"2815 Exposition Blvd\",\n    \"street2\": \"Ste 2353242\",\n    \"street3\": null,\n    \"city\": \"Austin\",\n    \"state\": \"TX\",\n    \"postalCode\": \"78703\",\n    \"country\": \"US\",\n    \"phone\": null,\n    \"residential\": false\n  },\n  \"shipTo\": {\n    \"name\": \"The President\",\n    \"company\": \"US Govt\",\n    \"street1\": \"1600 Pennsylvania Ave\",\n    \"street2\": \"Oval Office\",\n    \"street3\": null,\n    \"city\": \"Washington\",\n    \"state\": \"DC\",\n    \"postalCode\": \"20500\",\n    \"country\": \"US\",\n    \"phone\": null,\n    \"residential\": false\n  },\n  \"insuranceOptions\": null,\n  \"internationalOptions\": null,\n  \"advancedOptions\": null,\n  \"testLabel\": false\n}",  ParameterType.RequestBody);
IRestResponse response = client.Execute(request);
Console.WriteLine(response.Content);

OkHttpClient client = new OkHttpClient().newBuilder()
  .build();
MediaType mediaType = MediaType.parse("application/json");
RequestBody body = RequestBody.create(mediaType, "{\n  \"carrierCode\": \"fedex\",\n  \"serviceCode\": \"fedex_ground\",\n  \"packageCode\": \"package\",\n  \"confirmation\": \"delivery\",\n  \"shipDate\": \"2014-04-03\",\n  \"weight\": {\n    \"value\": 3,\n    \"units\": \"ounces\"\n  },\n  \"dimensions\": {\n    \"units\": \"inches\",\n    \"length\": 7,\n    \"width\": 5,\n    \"height\": 6\n  },\n  \"shipFrom\": {\n    \"name\": \"Jason Hodges\",\n    \"company\": \"ShipStation\",\n    \"street1\": \"2815 Exposition Blvd\",\n    \"street2\": \"Ste 2353242\",\n    \"street3\": null,\n    \"city\": \"Austin\",\n    \"state\": \"TX\",\n    \"postalCode\": \"78703\",\n    \"country\": \"US\",\n    \"phone\": null,\n    \"residential\": false\n  },\n  \"shipTo\": {\n    \"name\": \"The President\",\n    \"company\": \"US Govt\",\n    \"street1\": \"1600 Pennsylvania Ave\",\n    \"street2\": \"Oval Office\",\n    \"street3\": null,\n    \"city\": \"Washington\",\n    \"state\": \"DC\",\n    \"postalCode\": \"20500\",\n    \"country\": \"US\",\n    \"phone\": null,\n    \"residential\": false\n  },\n  \"insuranceOptions\": null,\n  \"internationalOptions\": null,\n  \"advancedOptions\": null,\n  \"testLabel\": false\n}");
Request request = new Request.Builder()
  .url("https://ssapi.shipstation.com/shipments/createlabel")
  .method("POST", body)
  .addHeader("Host", "ssapi.shipstation.com")
  .addHeader("Authorization", "__YOUR_AUTH_HERE__")
  .addHeader("Content-Type", "application/json")
  .build();
Response response = client.newCall(request).execute();

package main

import (
  "fmt"
  "strings"
  "net/http"
  "io/ioutil"
)

func main() {

  url := "https://ssapi.shipstation.com/shipments/createlabel"
  method := "POST"

  payload := strings.NewReader("{\n  \"carrierCode\": \"fedex\",\n  \"serviceCode\": \"fedex_ground\",\n  \"packageCode\": \"package\",\n  \"confirmation\": \"delivery\",\n  \"shipDate\": \"2014-04-03\",\n  \"weight\": {\n    \"value\": 3,\n    \"units\": \"ounces\"\n  },\n  \"dimensions\": {\n    \"units\": \"inches\",\n    \"length\": 7,\n    \"width\": 5,\n    \"height\": 6\n  },\n  \"shipFrom\": {\n    \"name\": \"Jason Hodges\",\n    \"company\": \"ShipStation\",\n    \"street1\": \"2815 Exposition Blvd\",\n    \"street2\": \"Ste 2353242\",\n    \"street3\": null,\n    \"city\": \"Austin\",\n    \"state\": \"TX\",\n    \"postalCode\": \"78703\",\n    \"country\": \"US\",\n    \"phone\": null,\n    \"residential\": false\n  },\n  \"shipTo\": {\n    \"name\": \"The President\",\n    \"company\": \"US Govt\",\n    \"street1\": \"1600 Pennsylvania Ave\",\n    \"street2\": \"Oval Office\",\n    \"street3\": null,\n    \"city\": \"Washington\",\n    \"state\": \"DC\",\n    \"postalCode\": \"20500\",\n    \"country\": \"US\",\n    \"phone\": null,\n    \"residential\": false\n  },\n  \"insuranceOptions\": null,\n  \"internationalOptions\": null,\n  \"advancedOptions\": null,\n  \"testLabel\": false\n}")

  client := &http.Client {
  }
  req, err := http.NewRequest(method, url, payload)

  if err != nil {
    fmt.Println(err)
  }
  req.Header.Add("Host", "ssapi.shipstation.com")
  req.Header.Add("Authorization", "__YOUR_AUTH_HERE__")
  req.Header.Add("Content-Type", "application/json")

  res, err := client.Do(req)
  defer res.Body.Close()
  body, err := ioutil.ReadAll(res.Body)

  fmt.Println(string(body))
}

#import <Foundation/Foundation.h>

dispatch_semaphore_t sema = dispatch_semaphore_create(0);

NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:[NSURL URLWithString:@"https://ssapi.shipstation.com/shipments/createlabel"]
  cachePolicy:NSURLRequestUseProtocolCachePolicy
  timeoutInterval:10.0];
NSDictionary *headers = @{
  @"Host": @"ssapi.shipstation.com",
  @"Authorization": @"__YOUR_AUTH_HERE__",
  @"Content-Type": @"application/json"
};

[request setAllHTTPHeaderFields:headers];
NSData *postData = [[NSData alloc] initWithData:[@"{\n  \"carrierCode\": \"fedex\",\n  \"serviceCode\": \"fedex_ground\",\n  \"packageCode\": \"package\",\n  \"confirmation\": \"delivery\",\n  \"shipDate\": \"2014-04-03\",\n  \"weight\": {\n    \"value\": 3,\n    \"units\": \"ounces\"\n  },\n  \"dimensions\": {\n    \"units\": \"inches\",\n    \"length\": 7,\n    \"width\": 5,\n    \"height\": 6\n  },\n  \"shipFrom\": {\n    \"name\": \"Jason Hodges\",\n    \"company\": \"ShipStation\",\n    \"street1\": \"2815 Exposition Blvd\",\n    \"street2\": \"Ste 2353242\",\n    \"street3\": null,\n    \"city\": \"Austin\",\n    \"state\": \"TX\",\n    \"postalCode\": \"78703\",\n    \"country\": \"US\",\n    \"phone\": null,\n    \"residential\": false\n  },\n  \"shipTo\": {\n    \"name\": \"The President\",\n    \"company\": \"US Govt\",\n    \"street1\": \"1600 Pennsylvania Ave\",\n    \"street2\": \"Oval Office\",\n    \"street3\": null,\n    \"city\": \"Washington\",\n    \"state\": \"DC\",\n    \"postalCode\": \"20500\",\n    \"country\": \"US\",\n    \"phone\": null,\n    \"residential\": false\n  },\n  \"insuranceOptions\": null,\n  \"internationalOptions\": null,\n  \"advancedOptions\": null,\n  \"testLabel\": false\n}" dataUsingEncoding:NSUTF8StringEncoding]];
[request setHTTPBody:postData];

[request setHTTPMethod:@"POST"];

NSURLSession *session = [NSURLSession sharedSession];
NSURLSessionDataTask *dataTask = [session dataTaskWithRequest:request
completionHandler:^(NSData *data, NSURLResponse *response, NSError *error) {
  if (error) {
    NSLog(@"%@", error);
  } else {
    NSHTTPURLResponse *httpResponse = (NSHTTPURLResponse *) response;
    NSError *parseError = nil;
    NSDictionary *responseDictionary = [NSJSONSerialization JSONObjectWithData:data options:0 error:&parseError];
    NSLog(@"%@",responseDictionary);
    dispatch_semaphore_signal(sema);
  }
}];
[dataTask resume];
dispatch_semaphore_wait(sema, DISPATCH_TIME_FOREVER);

import Foundation

var semaphore = DispatchSemaphore (value: 0)

let parameters = "{\n  \"carrierCode\": \"fedex\",\n  \"serviceCode\": \"fedex_ground\",\n  \"packageCode\": \"package\",\n  \"confirmation\": \"delivery\",\n  \"shipDate\": \"2014-04-03\",\n  \"weight\": {\n    \"value\": 3,\n    \"units\": \"ounces\"\n  },\n  \"dimensions\": {\n    \"units\": \"inches\",\n    \"length\": 7,\n    \"width\": 5,\n    \"height\": 6\n  },\n  \"shipFrom\": {\n    \"name\": \"Jason Hodges\",\n    \"company\": \"ShipStation\",\n    \"street1\": \"2815 Exposition Blvd\",\n    \"street2\": \"Ste 2353242\",\n    \"street3\": null,\n    \"city\": \"Austin\",\n    \"state\": \"TX\",\n    \"postalCode\": \"78703\",\n    \"country\": \"US\",\n    \"phone\": null,\n    \"residential\": false\n  },\n  \"shipTo\": {\n    \"name\": \"The President\",\n    \"company\": \"US Govt\",\n    \"street1\": \"1600 Pennsylvania Ave\",\n    \"street2\": \"Oval Office\",\n    \"street3\": null,\n    \"city\": \"Washington\",\n    \"state\": \"DC\",\n    \"postalCode\": \"20500\",\n    \"country\": \"US\",\n    \"phone\": null,\n    \"residential\": false\n  },\n  \"insuranceOptions\": null,\n  \"internationalOptions\": null,\n  \"advancedOptions\": null,\n  \"testLabel\": false\n}"
let postData = parameters.data(using: .utf8)

var request = URLRequest(url: URL(string: "https://ssapi.shipstation.com/shipments/createlabel")!,timeoutInterval: Double.infinity)
request.addValue("ssapi.shipstation.com", forHTTPHeaderField: "Host")
request.addValue("__YOUR_AUTH_HERE__", forHTTPHeaderField: "Authorization")
request.addValue("application/json", forHTTPHeaderField: "Content-Type")

request.httpMethod = "POST"
request.httpBody = postData

let task = URLSession.shared.dataTask(with: request) { data, response, error in 
  guard let data = data else {
    print(String(describing: error))
    return
  }
  print(String(data: data, encoding: .utf8)!)
  semaphore.signal()
}

task.resume()
semaphore.wait()

Example Response

{
  "shipmentId": 123456789,
  "orderId": null,
  "userId": null,
  "customerEmail": null,
  "orderNumber": null,
  "createDate": "2016-04-03T12:11:36.8630000",
  "shipDate": "2016-04-03",
  "shipmentCost": 9.06,
  "insuranceCost": 0,
  "trackingNumber": "782390443992",
  "isReturnLabel": false,
  "batchNumber": null,
  "carrierCode": "fedex",
  "serviceCode": "fedex_ground",
  "packageCode": "package",
  "confirmation": "delivery",
  "warehouseId": null,
  "voided": false,
  "voidDate": null,
  "marketplaceNotified": false,
  "notifyErrorMessage": null,
  "shipTo": null,
  "weight": null,
  "dimensions": null,
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