diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..7a8a0ad
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,3 @@
+composer.phar
+composer.lock
+vendor
diff --git a/composer.json b/composer.json
new file mode 100644
index 0000000..45a9d0f
--- /dev/null
+++ b/composer.json
@@ -0,0 +1,22 @@
+{
+    "name": "ariselseng/norwegianbanks",
+    "autoload": {
+        "psr-4": {
+            "Ariselseng\\NorwegianBanks\\": "src/"
+        }
+    },
+    "require": {
+        "phpoffice/phpspreadsheet": "^1.9",
+        "komakino/modulus11": "^1.0",
+        "desarrolla2/cache": "^3.0",
+        "guzzlehttp/guzzle": "^6.5"
+    },
+    "require-dev": {
+        "phpunit/phpunit": "4.*"
+    },
+    "autoload-dev": {
+        "psr-4": {
+            "Ariselseng\\NorwegianBanks\\Tests\\": "tests/"
+        }
+    }
+}
diff --git a/phpunit.xml b/phpunit.xml
new file mode 100644
index 0000000..b423a7e
--- /dev/null
+++ b/phpunit.xml
@@ -0,0 +1,19 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<phpunit backupGlobals="false"
+         backupStaticAttributes="false"
+         bootstrap="vendor/autoload.php"
+         colors="true"
+         convertErrorsToExceptions="true"
+         convertNoticesToExceptions="true"
+         convertWarningsToExceptions="true"
+         processIsolation="false"
+         stopOnFailure="false"
+         syntaxCheck="false"
+         verbose="true"
+        >
+    <testsuites>
+        <testsuite name="Package Test Suite">
+            <directory suffix=".php">./tests/</directory>
+        </testsuite>
+    </testsuites>
+</phpunit>
diff --git a/src/NorwegianBank.php b/src/NorwegianBank.php
new file mode 100644
index 0000000..2bf939b
--- /dev/null
+++ b/src/NorwegianBank.php
@@ -0,0 +1,21 @@
+<?php
+
+namespace Ariselseng\NorwegianBanks;
+
+
+class NorwegianBank
+{
+    public $bankCode;
+    public $bankName;
+    public $prefixes;
+
+    function __construct(string $bankCode, string $bankName, array $prefixes = [])
+    {
+        $this->bankCode = $bankCode;
+        $this->bankName = $bankName;
+        $this->prefixes = $prefixes;
+    }
+    public function addPrefix(string $prefix) {
+        $this->prefixes[] = $prefix;
+    }
+}
diff --git a/src/NorwegianBanks.php b/src/NorwegianBanks.php
new file mode 100644
index 0000000..5e98cd6
--- /dev/null
+++ b/src/NorwegianBanks.php
@@ -0,0 +1,139 @@
+<?php
+
+namespace Ariselseng\NorwegianBanks;
+
+use Komakino\Modulus11\Modulus11;
+use Desarrolla2\Cache\File as FileCache;
+
+class NorwegianBanks
+{
+    private const XlsFileUrl = 'https://www.finansnorge.no/contentassets/cc4fabf26cea4569aa447aa9ae671efa/norwegian-iban-bic-table.xls';
+    private const xlsFileTtl = 1440;
+
+    private $xlsFilePath;
+    private $banks;
+    private $prefixToBankCode;
+
+    public function __construct()
+    {
+        $this->xlsFilePath = sys_get_temp_dir() . '/.cache-norwegianbanks-norwegian-iban-bic-table.xls';
+        $this->processData();
+    }
+
+    private function downloadData()
+    {
+
+        $xlsFileExists = file_exists($this->xlsFilePath);
+        if ($xlsFileExists && filemtime($this->xlsFilePath) <= (time() - self::xlsFileTtl)) {
+            $headers = [
+                'If-Modified-Since' => gmdate('D, d M Y H:i:s T', filemtime($this->xlsFilePath)),
+            ];
+        } else if (!$xlsFileExists) {
+            $headers = null;
+            
+        } else {
+            return;
+        }
+
+        $response = (new \GuzzleHttp\Client())->get(self::XlsFileUrl, [
+            'headers' => $headers,
+        ]);
+
+        if ($response->getStatusCode() === 200 && $response->getBody()->getSize() > 0) {
+            file_put_contents($this->xlsFilePath, $response->getBody()->getContents(), LOCK_EX);
+        }
+    }
+
+    private function processData()
+    {
+        $this->downloadData();
+        $cacheDir = sys_get_temp_dir() . '/phpcache-norwegianbanks-' . filemtime($this->xlsFilePath);
+        $hasCacheDir = file_exists($cacheDir);
+        if (!$hasCacheDir) {
+            $hasCacheDir = mkdir($cacheDir);
+        }
+
+        if ($hasCacheDir) {
+            $cache = new FileCache($cacheDir);
+            $banks = $cache->get('banks');
+        }
+
+        if (!$hasCacheDir || !isset($banks)) {
+            $banks = [];
+            $prefixToBankCode = [];
+            $reader = \PhpOffice\PhpSpreadsheet\IOFactory::createReader("Xls");
+            $reader->setReadDataOnly(true);
+
+            $spreadsheet = $reader->load($this->xlsFilePath);
+            $worksheet = $spreadsheet->getActiveSheet();
+            $rows = $worksheet->toArray(null, false, false, false);
+
+            for ($i = 0; $i < count($rows); $i++) {
+                if (is_null($rows[$i][1])) {
+                    continue;
+                }
+                if (!isset($banks[$rows[$i][1]])) {
+                    $banks[$rows[$i][1]] = new NorwegianBank($rows[$i][1], $rows[$i][2], [$rows[$i][0]]);
+                } else {
+                    $banks[$rows[$i][1]]->addPrefix($rows[$i][0]);
+                }
+                $prefixToBankCode[$rows[$i][0]] = $rows[$i][1];
+            }
+
+            if ($hasCacheDir) {
+                $cache->set('banks', $banks, self::xlsFileTtl);
+                $cache->set('prefixToBankCode', $prefixToBankCode, self::xlsFileTtl);
+            }
+
+            $this->banks = $banks;
+            $this->prefixToBankCode = $prefixToBankCode;
+        } else {
+            $this->banks = $banks;
+            $this->prefixToBankCode = $cache->get('prefixToBankCode');
+        }
+    }
+    public function getBankCodeByPrefix(string $prefix)
+    {
+
+        if (!isset($this->prefixToBankCode[$prefix])) {
+            return null;
+        }
+        return $this->prefixToBankCode[$prefix];
+    }
+
+    public function getBankByAccountNumber(string $account)
+    {
+        $prefix = substr($account, 0, 4);
+        $bankCode = $this->getBankCodeByPrefix($prefix);
+        if (is_null($bankCode)) {
+            return null;
+        }
+        return $this->banks[$this->getBankCodeByPrefix($prefix)];
+    }
+
+    public function getFormattedAccountNumber(string $unformattedAccount, string $delimiter = '.')
+    {
+        $onlyDigits = preg_replace('/[^0-9]/', '', $unformattedAccount);
+        return substr($onlyDigits, 0, 4) . $delimiter . substr($onlyDigits, 4, 2) . $delimiter . substr($onlyDigits, 6);
+    }
+
+    public function validateAccountNumber(string $account)
+    {
+        $mod11 = Modulus11::validate($account);
+
+        if (!$mod11) {
+            return false;
+        }
+
+        return !is_null($this->getBankByAccountNumber(substr($account, 0, 4)));
+    }
+}
+
+class NorwegianBanksStatic
+{
+    public static function __callStatic($method, $args)
+    {
+        $obj = new NorwegianBanks();
+        return $obj->$method(...$args);
+    }
+}
diff --git a/tests/NorwegianBanksTest.php b/tests/NorwegianBanksTest.php
new file mode 100644
index 0000000..5a4126e
--- /dev/null
+++ b/tests/NorwegianBanksTest.php
@@ -0,0 +1,78 @@
+<?php
+
+namespace Ariselseng\NorwegianBanks\Tests;
+
+use Ariselseng\NorwegianBanks\NorwegianBanks;
+use Ariselseng\NorwegianBanks\NorwegianBanksStatic;
+
+class NorwegianBanksTest extends \PHPUnit_Framework_TestCase
+{
+    protected $accounts = [
+        [
+            'bankCode' => 'DNBANOKK',
+            'number' => '1594 22 87248'
+        ],
+        [
+            'bankCode' => 'NDEANOKK',
+            'number' => '61050659274'
+        ],
+        [
+            'bankCode' => 'SPSONO22',
+            'number' => '3000.27.79419'
+        ],
+    ];
+    protected $notRealAccountNumber = '1234.56.78903';
+    protected $notRealAccountNumberWithSpaces = '1234 56 78903';
+    protected $notRealAccountNumberUnformatted = '12345678903';
+
+    private $norwegianBanks;
+
+    public function __construct()
+    {
+        $this->norwegianBanks = new NorwegianBanks();
+    }
+
+    public function testGetFormattedAccountNumber()
+    {
+        $this->assertEquals($this->notRealAccountNumber, $this->norwegianBanks->getFormattedAccountNumber($this->notRealAccountNumberUnformatted));
+        $this->assertEquals($this->notRealAccountNumber, NorwegianBanksStatic::getFormattedAccountNumber($this->notRealAccountNumberUnformatted));
+        $this->assertEquals($this->notRealAccountNumberWithSpaces, $this->norwegianBanks->getFormattedAccountNumber($this->notRealAccountNumberUnformatted, ' '));
+        $this->assertEquals($this->notRealAccountNumberWithSpaces, NorwegianBanksStatic::getFormattedAccountNumber($this->notRealAccountNumberUnformatted, ' '));
+    }
+
+    public function testGetBankCodeByPrefix()
+    {
+        foreach ($this->accounts as $account) {
+            $this->assertEquals($account['bankCode'], $this->norwegianBanks->getBankCodeByPrefix(substr($account['number'], 0, 4)));
+            $this->assertEquals($account['bankCode'], NorwegianBanksStatic::getBankCodeByPrefix(substr($account['number'], 0, 4)));
+        }
+        $this->assertEquals(null, $this->norwegianBanks->getBankCodeByPrefix('0000'));
+        $this->assertEquals(null, NorwegianBanksStatic::getBankCodeByPrefix('0000'));
+    }
+
+    public function testGetBankByAccountNumber()
+    {
+
+        foreach ($this->accounts as $account) {
+            $this->assertAttributeEquals($account['bankCode'], 'bankCode', $this->norwegianBanks->getBankByAccountNumber($account['number']));
+            $this->assertAttributeEquals($account['bankCode'], 'bankCode', NorwegianBanksStatic::getBankByAccountNumber($account['number']));
+        }
+
+        $this->assertEquals(null, $this->norwegianBanks->getBankByAccountNumber($this->notRealAccountNumber));
+        $this->assertEquals(null, NorwegianBanksStatic::getBankByAccountNumber($this->notRealAccountNumber));
+    }
+
+    public function testValidate()
+    {
+
+        foreach ($this->accounts as $account) {
+            $this->assertTrue($this->norwegianBanks->validateAccountNumber($account['number']));
+            $this->assertTrue(NorwegianBanksStatic::validateAccountNumber($account['number']));
+
+        }
+
+        $this->assertFalse($this->norwegianBanks->validateAccountNumber($this->notRealAccountNumber));
+        $this->assertFalse(NorwegianBanksStatic::validateAccountNumber($this->notRealAccountNumber));
+
+    }
+}