diff --git a/src/Builder/Pdf/AbstractPdfBuilder.php b/src/Builder/Pdf/AbstractPdfBuilder.php
index b72e8b00..5796c2ae 100644
--- a/src/Builder/Pdf/AbstractPdfBuilder.php
+++ b/src/Builder/Pdf/AbstractPdfBuilder.php
@@ -72,7 +72,7 @@ public function __construct(
             },
         ];
 
-        $this->operationIdGenerator = static fn (): string => uniqid('gotenberg_', true);
+        $this->operationIdGenerator = static fn (): string => 'gotenberg_'.bin2hex(random_bytes(16)).microtime(true);
     }
 
     public function setLogger(LoggerInterface|null $logger): void
diff --git a/src/Builder/Screenshot/AbstractScreenshotBuilder.php b/src/Builder/Screenshot/AbstractScreenshotBuilder.php
index 7625a625..a70f5121 100644
--- a/src/Builder/Screenshot/AbstractScreenshotBuilder.php
+++ b/src/Builder/Screenshot/AbstractScreenshotBuilder.php
@@ -63,7 +63,7 @@ public function __construct(
             },
         ];
 
-        $this->operationIdGenerator = fn () => uniqid('gotenberg_', true);
+        $this->operationIdGenerator = static fn (): string => 'gotenberg_'.bin2hex(random_bytes(16)).microtime(true);
     }
 
     public function setLogger(LoggerInterface|null $logger): void