diff --git a/src/samplecounter.cpp b/src/samplecounter.cpp
new file mode 100644
--- /dev/null
+++ b/src/samplecounter.cpp
@@ -0,0 +1,44 @@
+/*
+  Copyright © 2018 Hasan Yavuz Özderya
+
+  This file is part of serialplot.
+
+  serialplot is free software: you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation, either version 3 of the License, or
+  (at your option) any later version.
+
+  serialplot is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with serialplot.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include <QDateTime>
+#include "samplecounter.h"
+
+SampleCounter::SampleCounter()
+{
+    prevTimeMs = QDateTime::currentMSecsSinceEpoch();
+    count = 0;
+}
+
+#include <QtDebug>
+
+void SampleCounter::feedIn(const SamplePack& data)
+{
+    count += data.numSamples();
+
+    qint64 current = QDateTime::currentMSecsSinceEpoch();
+    auto diff = current - prevTimeMs;
+    if (diff > 1000) // 1sec
+    {
+        emit spsChanged(1000 * float(count) / diff);
+
+        prevTimeMs = current;
+        count = 0;
+    }
+}