diff --git a/4dev/tests/Create/CoreLibsCreateCrc64Test.php b/4dev/tests/Create/CoreLibsCreateCrc64Test.php
new file mode 100644
index 00000000..dffa02a7
--- /dev/null
+++ b/4dev/tests/Create/CoreLibsCreateCrc64Test.php
@@ -0,0 +1,73 @@
+<?php
+
+declare(strict_types=1);
+
+namespace tests;
+
+use PHPUnit\Framework\TestCase;
+
+/**
+ * Test class for Create\Crc64
+ * @coversDefaultClass \CoreLibs\Create\Crc64
+ * @testdox \CoreLibs\Create\Crc64 method tests
+ */
+final class CoreLibsCreateCrc64Test extends TestCase
+{
+	public function providerFiles(): array
+	{
+		return [
+			'10kb' => [
+				'file' => __DIR__ . DIRECTORY_SEPARATOR . 'files' . DIRECTORY_SEPARATOR . 'random_10KB.bin',
+				'crc64_base64' => 'oMgkUkGrDME=',
+				'crc64_hex' => 'a0c8245241ab0cc1',
+			],
+			'100kb' => [
+				'file' => __DIR__ . DIRECTORY_SEPARATOR . 'files' . DIRECTORY_SEPARATOR . 'random_100KB.bin',
+				'crc64_base64' => 'i9Lpf3Y3D3M=',
+				'crc64_hex' => '8bd2e97f76370f73',
+			],
+			'1mb' => [
+				'file' => __DIR__ . DIRECTORY_SEPARATOR . 'files' . DIRECTORY_SEPARATOR . 'random_1MB.bin',
+				'crc64_base64' => 'WqYAirRJ0q8=',
+				'crc64_hex' => '5aa6008ab449d2af',
+			],
+			'5mb' => [
+				'file' => __DIR__ . DIRECTORY_SEPARATOR . 'files' . DIRECTORY_SEPARATOR . 'random_5MB.bin',
+				'crc64_base64' => '9hS5kUxbgR0=',
+				'crc64_hex' => 'f614b9914c5b811d',
+			],
+			'10mb' => [
+				'file' => __DIR__ . DIRECTORY_SEPARATOR . 'files' . DIRECTORY_SEPARATOR . 'random_10MB.bin',
+				'crc64_base64' => 'xDmtkk1JhjM=',
+				'crc64_hex' => 'c439ad924d498633',
+			],
+			// everything above 10MB is too slow, sow do not check this
+		];
+	}
+
+	/**
+	 * Undocumented function
+	 *
+	 * @covers ::crc64
+	 * @covers ::crc64hex
+	 * @dataProvider providerFiles
+	 * @testdox generate crc64 for $file and expecting $crc64_base64 and $crc64_hex [$_dataName]
+	 *
+	 * @return void
+	 */
+	public function testCrc64(string $file, string $crc64_base64, string $crc64_hex): void
+	{
+		$this->assertSame(
+			$crc64_base64,
+			\CoreLibs\Create\Crc64::crc64($file),
+			"Failed asserting base64 CRC64 for $file"
+		);
+		$this->assertSame(
+			$crc64_hex,
+			\CoreLibs\Create\Crc64::crc64hex($file),
+			"Failed asserting hex CRC64 for $file"
+		);
+	}
+}
+
+// __END__
diff --git a/4dev/tests/Create/files/random_100KB.bin b/4dev/tests/Create/files/random_100KB.bin
new file mode 100644
index 00000000..c9ab5eab
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diff --git a/4dev/tests/Create/files/random_10KB.bin b/4dev/tests/Create/files/random_10KB.bin
new file mode 100644
index 00000000..c6d3b8c4
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diff --git a/4dev/tests/Create/files/random_10MB.bin b/4dev/tests/Create/files/random_10MB.bin
new file mode 100644
index 00000000..81f205dc
Binary files /dev/null and b/4dev/tests/Create/files/random_10MB.bin differ
diff --git a/4dev/tests/Create/files/random_1MB.bin b/4dev/tests/Create/files/random_1MB.bin
new file mode 100644
index 00000000..0002c672
Binary files /dev/null and b/4dev/tests/Create/files/random_1MB.bin differ
diff --git a/4dev/tests/Create/files/random_5MB.bin b/4dev/tests/Create/files/random_5MB.bin
new file mode 100644
index 00000000..796bfda0
Binary files /dev/null and b/4dev/tests/Create/files/random_5MB.bin differ
diff --git a/www/admin/class_test.crc64.php b/www/admin/class_test.crc64.php
new file mode 100644
index 00000000..9d389dc6
--- /dev/null
+++ b/www/admin/class_test.crc64.php
@@ -0,0 +1,77 @@
+<?php // phpcs:ignore warning
+
+/**
+ * @phan-file-suppress PhanTypeSuspiciousStringExpression
+ */
+
+declare(strict_types=1);
+
+error_reporting(E_ALL | E_ERROR | E_WARNING | E_PARSE | E_COMPILE_ERROR);
+
+ob_start();
+
+// basic class test file
+define('USE_DATABASE', false);
+// sample config
+require 'config.php';
+// define log file id
+$LOG_FILE_ID = 'classTest-crc64';
+ob_end_flush();
+
+use CoreLibs\Create\Crc64;
+use CoreLibs\Debug\RunningTime;
+
+$log = new CoreLibs\Logging\Logging([
+	'log_folder' => BASE . LOG,
+	'log_file_id' => $LOG_FILE_ID,
+	'log_per_date' => true,
+]);
+
+$PAGE_NAME = 'TEST CLASS: CRC64';
+print "<!DOCTYPE html>";
+print "<html><head><title>" . $PAGE_NAME . "</title></head>";
+print "<body>";
+print '<div><a href="class_test.php">Class Test Master</a></div>';
+print '<div><h1>' . $PAGE_NAME . '</h1></div>';
+
+
+$file = getcwd() . DIRECTORY_SEPARATOR . 'class_test.file.php';
+print "CRC64: $file: " . Crc64::crc64($file) . "<br>";
+print "CRC64HEX: $file: " . Crc64::crc64hex($file) . "<br>";
+
+// big file check including speed
+$base_path = __DIR__ . DIRECTORY_SEPARATOR
+	. '..' . DIRECTORY_SEPARATOR
+	. '..' . DIRECTORY_SEPARATOR
+	. '4dev' . DIRECTORY_SEPARATOR . 'tests' . DIRECTORY_SEPARATOR .
+	'Create' . DIRECTORY_SEPARATOR . 'files' . DIRECTORY_SEPARATOR;
+$max_size = 1024 * 1024 * 10;
+# open the base path and loop over each file in there
+$files = glob($base_path . '*');
+if (!empty($files)) {
+	foreach ($files as $file) {
+		if (!is_file($file)) {
+			continue;
+		}
+		if (filesize($file) > $max_size) {
+			print "Skipping large file: $file<br>";
+			continue;
+		}
+		RunningTime::runningTime();
+		print "CRC64: $file: " . Crc64::crc64($file) . "<br>";
+		RunningTime::runningTime();
+		print "Running Time: $file: " . RunningTime::runningTimeString() . "<br>";
+		print "Running Time: $file: " . RunningTime::hrRunningTime() . "<br>";
+		print "CRC64HEX: $file: " . Crc64::crc64hex($file) . "<br>";
+		RunningTime::runningTime();
+		print "Running Time: $file: " . RunningTime::runningTimeString() . "<br>";
+		print "Running Time: $file: " . RunningTime::hrRunningTime() . "<br>";
+		RunningTime::hrRunningTimeReset();
+	}
+} else {
+	print "No files found in base path: $base_path<br>";
+}
+
+print "</body></html>";
+
+// __END__
diff --git a/www/admin/class_test.php b/www/admin/class_test.php
index 0e2d6ad4..2ae5c7ac 100644
--- a/www/admin/class_test.php
+++ b/www/admin/class_test.php
@@ -120,6 +120,7 @@ $test_files = [
 	'class_test.datetime.php' => 'Class Test: DATE/TIME',
 	'class_test.array.php' => 'Class Test: ARRAY HANDLER',
 	'class_test.file.php' => 'Class Test: FILE',
+	'class_test.crc64.php' => 'Class Test: CRC64',
 	'class_test.randomkey.php' => 'Class Test: RANDOM KEY',
 	'class_test.system.php' => 'Class Test: SYSTEM',
 	'class_test.readenvfile.php' => 'Class Test: READ ENV FILE',
diff --git a/www/lib/CoreLibs/Create/Crc64.php b/www/lib/CoreLibs/Create/Crc64.php
new file mode 100644
index 00000000..eab5ac45
--- /dev/null
+++ b/www/lib/CoreLibs/Create/Crc64.php
@@ -0,0 +1,106 @@
+<?php
+
+/**
+ * AUTHOR: Clemens Schwaighofer
+ * CREATED: 2026/10/15
+ * DESCRIPTION:
+ * AWS CRC64 Implementation
+ * This can be replaced by:
+ * https://github.com/awesomized/crc-fast-php-ext
+ * This this needs: https://github.com/awesomized/crc-fast-rust
+ * installed, and there is no easy binary package available.
+ *
+ * NOTE: for anything larger than 10MB this is absolutely NOT recommended
+*/
+
+declare(strict_types=1);
+
+namespace CoreLibs\Create;
+
+class Crc64
+{
+	/**
+	 * Internal CRC64 calculation for a given data string.
+	 *
+	 * @param  string $data
+	 * @param  int    $crc
+	 * @return int
+	 */
+	private function crc64Calc(string $data, int $crc = 0): int
+	{
+		static $table = null;
+		if ($table === null) {
+			// reflected poly 0x9A6C9329AC4BC9B5 (built from halves, too big for a PHP int literal)
+			$poly = (0x9A6C9329 << 32) | 0xAC4BC9B5;
+			$table = [];
+			for ($i = 0; $i < 256; $i++) {
+				$c = $i;
+				for ($k = 0; $k < 8; $k++) {
+					// logical right shift: PHP >> is arithmetic, so mask off the sign bit
+					$c = ($c & 1)
+						? ((($c >> 1) & PHP_INT_MAX) ^ $poly)
+						: (($c >> 1) & PHP_INT_MAX);
+				}
+				$table[$i] = $c;
+			}
+		}
+		$crc = ~$crc; // xor 0xFFFFFFFFFFFFFFFF
+		foreach (unpack('C*', $data) ?: [] as $b) {
+			$crc = $table[($crc ^ $b) & 0xFF] ^ (($crc >> 8) & 0x00FFFFFFFFFFFFFF);
+		}
+		return ~$crc;
+	}
+
+	/**
+	 * Returns int value of the CRC64 checksum for the given file.
+	 *
+	 * @param  string $path
+	 * @param  int<1,16777216> $chunkSize
+	 * @return int
+	 */
+	private function crc64CalcFile(string $path, int $chunkSize = 8 * 1024 * 1024): int
+	{
+		$fh = fopen($path, 'rb');
+		if ($fh === false) {
+			throw new \RuntimeException("Cannot open $path");
+		}
+		$crc = 0;
+		try {
+			while (!feof($fh)) {
+				$chunk = fread($fh, $chunkSize);
+				if ($chunk === false) {
+					throw new \RuntimeException("Read error on $path");
+				}
+				$crc = $this->crc64Calc($chunk, $crc);
+			}
+		} finally {
+			fclose($fh);
+		}
+		return $crc;
+	}
+
+	/**
+	 * Returns the Base64-encoded CRC64 checksum for the given file.
+	 *
+	 * @param  string $path
+	 * @return string
+	 */
+	public static function crc64(string $path): string
+	{
+		return base64_encode(pack('J', (new self())->crc64CalcFile($path))); // J = uint64 big-endian
+	}
+
+	/**
+	 * Returns the 16-character lowercase hexadecimal CRC64 checksum for the given file.
+	 * Same as base64.b64decode(...).hex()
+	 *
+	 * @param  string $path
+	 * @return string
+	 */
+	public static function crc64hex(string $path): string
+	{
+		return sprintf('%016x', (new self())->crc64CalcFile($path));
+	}
+}
+
+// __END__