diff --git a/src/samplecounter.h b/src/samplecounter.h
new file mode 100644
--- /dev/null
+++ b/src/samplecounter.h
@@ -0,0 +1,47 @@
+/*
+  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/>.
+*/
+
+#ifndef SAMPLECOUNTER_H
+#define SAMPLECOUNTER_H
+
+#include <QObject>
+#include "sink.h"
+
+/// A `Sink` class for counting and reporting number of samples per second.
+class SampleCounter : public QObject, public Sink
+{
+    Q_OBJECT
+
+public:
+    SampleCounter();
+
+protected:
+    // implementations for `Sink`
+    virtual void feedIn(const SamplePack& data);
+
+signals:
+    /// Emitted per second if SPS value has changed.
+    void spsChanged(float value);
+
+private:
+    qint64 prevTimeMs;
+    unsigned count;
+};
+
+#endif // SAMPLECOUNTER_H