diff --git a/CMakeLists.txt b/CMakeLists.txt
index 4453e15..25b338e 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -20,7 +20,7 @@ set(CMAKE_AUTORCC ON)
 
 # Adding headers explicity so they are displayed in Qt Creator
 set(HEADERS config.h imagewriter.h networkaccessmanagerfactory.h nan.h drivelistitem.h drivelistmodel.h driveformatthread.h powersaveblocker.h
-    downloadthread.h downloadextractthread.h dependencies/mountutils/src/mountutils.hpp)
+    downloadthread.h downloadextractthread.h acceleratedcryptographichash.h dependencies/mountutils/src/mountutils.hpp)
 
 # Add 3rd-party dependencies
 if (APPLE)
@@ -60,8 +60,9 @@ endif()
 
 set(SOURCES "main.cpp" "imagewriter.cpp" "networkaccessmanagerfactory.cpp"
     "drivelistitem.cpp" "drivelistmodel.cpp" "downloadthread.cpp" "downloadextractthread.cpp"
-     "driveformatthread.cpp" "powersaveblocker.cpp" "qml.qrc")
+     "driveformatthread.cpp" "powersaveblocker.cpp" "acceleratedcryptographichash.cpp" "qml.qrc")
 
+find_package(OpenSSL REQUIRED)
 find_package(Qt5 COMPONENTS Core Quick Widgets LinguistTools REQUIRED)
 
 #qt5_create_translation(QM_FILES ${CMAKE_SOURCE_DIR} i18n/rpi-imager_nl.ts i18n/rpi-imager_zh_cn.ts)
@@ -233,5 +234,5 @@ else()
     install(FILES linux/rpi-imager.desktop DESTINATION share/applications)
 endif()
 
-include_directories(${CURL_INCLUDE_DIR} ${LibArchive_INCLUDE_DIR})
-target_link_libraries(${PROJECT_NAME} Qt5::Core Qt5::Quick Qt5::Widgets ${CURL_LIBRARIES} ${LibArchive_LIBRARIES} ${ATOMIC_LIBRARY} ${EXTRALIBS})
+include_directories(${CURL_INCLUDE_DIR} ${LibArchive_INCLUDE_DIR} ${OPENSSL_INCLUDE_DIR})
+target_link_libraries(${PROJECT_NAME} Qt5::Core Qt5::Quick Qt5::Widgets ${CURL_LIBRARIES} ${LibArchive_LIBRARIES} ${OPENSSL_LIBRARIES} ${ATOMIC_LIBRARY} ${EXTRALIBS})
diff --git a/acceleratedcryptographichash.cpp b/acceleratedcryptographichash.cpp
new file mode 100644
index 0000000..cade939
--- /dev/null
+++ b/acceleratedcryptographichash.cpp
@@ -0,0 +1,37 @@
+/*
+ * Use OpenSSL for hashing as their code is more optimized than Qt's
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ * Copyright (C) 2020 Raspberry Pi (Trading) Limited
+ */
+
+#include "acceleratedcryptographichash.h"
+
+AcceleratedCryptographicHash::AcceleratedCryptographicHash(QCryptographicHash::Algorithm method)
+{
+    if (method != QCryptographicHash::Sha256)
+        throw std::runtime_error("Only sha256 implemented");
+
+    SHA256_Init(&_sha256);
+}
+
+AcceleratedCryptographicHash::~AcceleratedCryptographicHash()
+{
+}
+
+void AcceleratedCryptographicHash::addData(const char *data, int length)
+{
+    SHA256_Update(&_sha256, data, length);
+}
+
+void AcceleratedCryptographicHash::addData(const QByteArray &data)
+{
+    addData(data.constData(), data.size());
+}
+
+QByteArray AcceleratedCryptographicHash::result()
+{
+    unsigned char binhash[SHA256_DIGEST_LENGTH];
+    SHA256_Final(binhash, &_sha256);
+    return QByteArray((char *) binhash, sizeof binhash);
+}
diff --git a/acceleratedcryptographichash.h b/acceleratedcryptographichash.h
new file mode 100644
index 0000000..4e87227
--- /dev/null
+++ b/acceleratedcryptographichash.h
@@ -0,0 +1,25 @@
+#ifndef ACCELERATEDCRYPTOGRAPHICHASH_H
+#define ACCELERATEDCRYPTOGRAPHICHASH_H
+
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ * Copyright (C) 2020 Raspberry Pi (Trading) Limited
+ */
+
+#include <QCryptographicHash>
+#include "openssl/sha.h"
+
+class AcceleratedCryptographicHash
+{
+public:
+    explicit AcceleratedCryptographicHash(QCryptographicHash::Algorithm method);
+    virtual ~AcceleratedCryptographicHash();
+    void addData(const char *data, int length);
+    void addData(const QByteArray &data);
+    QByteArray result();
+
+protected:
+    SHA256_CTX _sha256;
+};
+
+#endif // ACCELERATEDCRYPTOGRAPHICHASH_H
diff --git a/downloadextractthread.h b/downloadextractthread.h
index 0fc7a07..1d7e6bf 100644
--- a/downloadextractthread.h
+++ b/downloadextractthread.h
@@ -41,7 +41,7 @@ protected:
     std::mutex _queueMutex;
     std::condition_variable _cv;
     bool _ethreadStarted, _isImage;
-    QCryptographicHash _inputHash;
+    AcceleratedCryptographicHash _inputHash;
     int _activeBuf;
     bool _writeThreadStarted;
     QFuture<size_t> _writeFuture;
diff --git a/downloadthread.cpp b/downloadthread.cpp
index 2ed035b..8a62e4e 100644
--- a/downloadthread.cpp
+++ b/downloadthread.cpp
@@ -600,6 +600,8 @@ bool DownloadThread::_verify()
     char *verifyBuf = (char *) qMallocAligned(IMAGEWRITER_VERIFY_BLOCKSIZE, 4096);
     _lastVerifyNow = 0;
     _verifyTotal = _file.pos();
+    QElapsedTimer t1;
+    t1.start();
 
     if (!_firstBlock)
     {
@@ -627,6 +629,7 @@ bool DownloadThread::_verify()
     }
     qFreeAligned(verifyBuf);
 
+    qDebug() << "Verify done in" << t1.elapsed() / 1000.0 << "seconds";
     qDebug() << "Verify hash:" << _verifyhash.result().toHex();
 
     if (_verifyhash.result() == _writehash.result() || !_verifyEnabled || _cancelled)
diff --git a/downloadthread.h b/downloadthread.h
index 98b3931..896ecf6 100644
--- a/downloadthread.h
+++ b/downloadthread.h
@@ -9,12 +9,12 @@
 #include <QString>
 #include <QThread>
 #include <QFile>
-#include <QCryptographicHash>
 #include <QElapsedTimer>
 #include <fstream>
 #include <atomic>
 #include <time.h>
 #include <curl/curl.h>
+#include "acceleratedcryptographichash.h"
 
 #ifdef Q_OS_WIN
 #include "windows/winfile.h"
@@ -172,7 +172,7 @@ protected:
 #endif
     QFile _cachefile;
 
-    QCryptographicHash _writehash, _verifyhash;
+    AcceleratedCryptographicHash _writehash, _verifyhash;
 };
 
 #endif // DOWNLOADTHREAD_H