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Welcome to the Plate Recognizer API! You can use our API to access our API endpoints, which can read license plates from images. For detailed instructions on how to install the SDK, go here.

We have multiple language bindings. You can view code examples in the dark area to the right, and you can switch the programming language of the examples with the tabs in the top right.


Plate Recognizer API is only available to registered users. You first have to register and get an API key. It has to be included in all API calls. The HTTP headers must contain:

Authorization: Token API_TOKEN

License Plate Recognition

Read Number Plates from an Image

# gem install multipart-post
require 'net/http/post/multipart'

url = URI.parse('')
path = '/path/to/car.jpg' do |jpg|
  req = url.path,
    "upload" =>, "image/jpeg", path)
  req['Authorization'] = 'Token API_TOKEN'
  res = Net::HTTP.start(, url.port, use_ssl: true) do |http|
$file = realpath('example.jpg');
if (function_exists('curl_file_create')) { // php 5.5+
  $cFile = curl_file_create($file);
} else {
  $cFile = '@' . realpath($file);

$data = array(
    'upload' => $cFile,
    'regions' => 'fr' // Optional

// Prepare new cURL resource
$ch = curl_init('');
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLINFO_HEADER_OUT, true);
curl_setopt($ch, CURLOPT_POST, true);
curl_setopt($ch, CURLOPT_POSTFIELDS, $data);

// Set HTTP Header for POST request
curl_setopt($ch, CURLOPT_HTTPHEADER, array(
    "Authorization: Token API_TOKEN"  //API KEY

// Submit the POST request and close cURL session handle
$result = curl_exec($ch);
# pip install requests
import requests
from pprint import pprint
regions = ['fr', 'it']
with open('/path/to/car.jpg', 'rb') as fp:
    response =
        data=dict(regions=regions),  # Optional
        headers={'Authorization': 'Token API_TOKEN'})

curl -F 'upload=@/path/to/car.jpg' \
  -H 'Authorization: Token API_TOKEN' \

# You may also include regions
curl -F 'upload=@/path/to/car.jpg' \
  -F regions=fr -F regions=us-ca \
  -H 'Authorization: Token API_TOKEN' \

const fetch = require('node-fetch');
const FormData = require('form-data');
const fs = require('fs');

let image_path = '/path/to/car.jpg'
let body = new FormData();
body.append('upload', fs.createReadStream(image_path));

fetch("", {
        method: 'POST',
        headers: {
            "Authorization": "Token API_TOKEN"
        body: body
    }).then(res => res.json())
    .then(json => console.log(json))
    .catch((err) => {
// View the complete example here:

HttpWebRequest request = WebRequest.Create(postUrl) as HttpWebRequest;

// Set up the request properties.
request.Method = "POST";
request.ContentType = contentType;
request.UserAgent = ".NET Framework CSharp Client";
request.CookieContainer = new CookieContainer();
request.ContentLength = formData.Length;
request.Headers.Add("Authorization", "Token " + token);

// Send the form data to the request.
using (Stream requestStream = request.GetRequestStream())
    requestStream.Write(formData, 0, formData.Length);

HttpWebResponse response = (HttpWebResponse)request.GetResponse();

// View the complete example here:

String token = "MY_API_KEY";
String file = "C:\\assets\\demo.jpg";
  HttpResponse<String> response ="")
  .header("Authorization", "Token "+token)
  .field("upload", new File(file))
catch(Exception e){
// View the complete example here:
CURL *hnd = curl_easy_init();

//curl_easy_setopt(hnd, CURLOPT_CUSTOMREQUEST, "POST");
curl_easy_setopt(hnd, CURLOPT_URL, "");

form = curl_mime_init(hnd); //initialize form fields

/* Fill in the file upload field */
field = curl_mime_addpart(form);
curl_mime_name(field, "upload");
curl_mime_filedata(field, fileName.c_str());
curl_easy_setopt(hnd, CURLOPT_MIMEPOST, form);

Return value


This endpoint reads all license plates from an image.

HTTP Request


POST Parameters

Parameter Required Description
upload Yes The file to be uploaded
regions No Match the license plate pattern of specific regions. This parameter can be used multiple times to specify more than one region. *
camera_id No Unique camera identifier.
timestamp No ISO 8601 timestamp. For example, 2019-08-19T13:11:25. The timestamp has to be in UTC.

* The regions parameter is used as a guide and the template will be ignored if the prediction differs too much from it. It works this way because we want to still be able to read plates from foreign vehicles. The system may sometimes mistake a local vehicle for a foreign one.

JSON Response

The response is a list of all the license plates found in the image. Each license plate has the following elements:

Attribute Description
results/plate Text of the license plate.
results/box Bounding box for the license plate. Coordinates in pixel of the top left and bottom right corners of the plate.
results/dscore Score for plate detection. Range [0, 1].
results/score Score for reading the license plate text. Range [0, 1].
results/vehicle/type Vehicle type: Ambulance, Bus, Car, Limousine, Motorcycle, Taxi, Truck, Van, Unknown.
results/region/code Region of license plate. Returns a code from the country list.

The value dscore is dependent on the type of image we are processing. For example, if the images are coming from a highway camera you may have a threshold of X for good license plate detection. But if images are coming from a parking lot you may have a threshold of Y. So a good dscore has to be determined based on the images you are sending to us.

Regions supported

The regions parameter can take one of the following codes. In addition to country, you can also provide a states to select more specific license plate patterns. States are only supported for USA and Australia.

Country Region code
Albania al
Andorra ad
Angola ao
Argentina ar
Armenia am
Australia au
Austria at
Azerbaijan az
Belarus by
Belgium be
Belize bz
Bolivia bo
Bosnia and Herzegovina ba
Brazil br
Brunei bn
Bulgaria bg
Canada ca
Chile cl
Columbia co
Costa Rica cr
Croatia hr
Cyprus cy
Czechia cz
Denmark dk
Ecuador ec
El Salvador sv
Estonia ee
Finland fi
France fr
French Guiana gf
Georgia ge
Germany de
Gibraltar gi
Greece gr
Guatamala gp
Guyana gy
Holy See va
Honduras hn
Hungary hu
Iceland is
Israel il
India in
Indonesia id
Ireland ie
Italy it
Jordan jo
Kazakhstan kz
Kenya ke
Korea, Republic of kr
Latvia lv
Lebanon lb
Liechtenstein li
Lithuania lt
Luxembourg lu
Malaysia my
Maldives mv
Malta mt
Mexico mx
Moldova, Republic of md
Monaco mc
Montenegro me
Nepal np
Netherlands nl
Nicaragua ni
Nigeria ng
North Macedonia mk
Norway no
Panama pa
Paraguay py
Peru pe
Philippines ph
Poland pl
Portugal pt
Qatar qa
Romania ro
Russian Federation ru
San Marino sm
Serbia rs
Singapore sg
Slovakia sk
Slovenia si
South Africa za
Spain es
Suriname sr
Sweden se
Switzerland ch
Tanzania tz
Turkey tr
Ukraine ua
United Arab Emirates ae
United Kingdom of Great Britain and Northern Ireland gb
United States of America us
Uraguay uy
Venezuela ve
Vietnam vn
Zambia zm


Australian states:

State Region code
New South Wales au-nsw
Queensland au-qld
South Australia au-sa
Tasmania au-tas
Victoria au-vic
Western Australia au-wa

United States of America states:

State Region code
Alabama us-al
Alaska us-ak
Arizona us-az
Arkansas us-ar
California us-ca
Colorado us-co
Connecticut us-ct
Delaware us-de
District of Columbia us-dc
Florida us-fl
Georgia us-ga
Hawaii us-hi
Idaho us-id
Illinois us-il
Indiana us-in
Iowa us-ia
Kansas us-ks
Kentucky us-ky
Louisiana us-la
Maine us-me
Maryland us-md
Massachusetts us-ma
Michigan us-mi
Minnesota us-mn
Mississippi us-ms
Missouri us-mo
Montana us-mt
Nebraska us-ne
Nevada us-nv
New Hampshire us-nh
New Jersey us-nj
New Mexico us-nm
New York us-ny
North Carolina us-nc
North Dakota us-nd
Ohio us-oh
Oklahoma us-ok
Oregon us-or
Pennsylvania us-pa
Rhode Island us-ri
South Carolina us-sc
South Dakota us-sd
Tennessee us-tn
Texas us-tx
Utah us-ut
Vermont us-vt
Virginia us-va
Washington us-wa
West Virginia us-wv
Wisconsin us-wi
Wyoming us-wy

Brazilian states:

State Region Code
Acre br-ac
Alagoas br-al
Amapá br-ap
Amazonas br-am
Bahia br-ba
Ceará br-ce
Distrito Federal br-df
Espírito Santo br-es
Goiás br-go
Manias Gerais br-mg
Maranhão br-ma
Mato Grosso do Sul br-ms
Mato Grosso br-mt
Pernambuco br-pe
Pará br-pa
Paraíba br-pb
Paraná br-pr
Piauí br-pi
Rio de Janeiro br-rj
Rio Grande do Norte br-rn
Rio Grande do Sul br-rs
Rondônia br-ro
Roraima br-rr
São Paulo br-sp
Sergipe br-se
Santa Catarina br_sc
Tocantins br-to


Return value


Our service is also available on-premises. Get started with the SDK. It has the same interface as the recognition API. Note that it is hosted locally.

HTTP Request

POST http://localhost:8080/alpr

Accepts the same parameters as the recognition API.

JSON Response

Returns the same parameters as the recognition API. In addition to that, it returns the number of calls used.


Example of POST payload

  "hook": {
    "target": "http://localhost:8081/",
    "id": 2,
    "event": "image.done"
  "data": {
    "processing_time": 0.186,
    "timestamp": "2019-08-31T14:22:06.983Z",
    "results": [
        "box": {
          "xmin": 563,
          "ymin": 530,
          "ymax": 579,
          "xmax": 702
        "plate": "765410",
        "score": 0.9131534678711563,
        "dscore": 0.4084282568529709
        "box": {
          "xmin": 563,
          "ymin": 530,
          "ymax": 579,
          "xmax": 702
        "plate": "830265",
        "score": 0.7700640306685624,
        "dscore": 0.8493143507578083
    "filename": "14_22_test.jpeg",
    "version": 1,
    "camera_id": null

Our service also have a webhook service that allows you to receive a HTTP POST request to a target URL of your choosing. To configure webhooks, go to webhooks settings page to manage your webhooks or add a new webhook target.

To quickly test out this feature, you can use the URL from a


Get number of recognition calls done during the current month.

HTTP Request


curl -H 'Authorization: Token API_TOKEN' \

Return value

  "usage": {
    "month": 1,
    "calls": 128,
    "year": 2019
  "total_calls": 2500

JSON Response

Attribute Description
calls Number of API calls made during the current period.
month Month of the current period.
year Year of the current period.
total_calls Maximum number of API calls you can make during the period. Need more? Upgrade.


Error Code Meaning
403 Forbidden -- Your API key is wrong.
413 Payload Too Large response status code indicates that the request entity is larger than limits defined by our server. See upload limits.
429 Indicates the user has sent too many requests in a given amount of time. Upgrade for higher number of calls per second.


Can't make it work? We may have answers on our FAQ.