I work on hourly basis.Is it o.k. if I work less than the claimed hours, even if no body cares about it.

It is not appropriate for us to comment until we have looked at your employment contract. Nevertheless, if you had entered into an agreement with your employer that you work for so many hours at a fixed rate, you will have to work accordingly. It is not permiisble to work for less hours and claim remuneration for the full hours. The time at work is Amaanat (trust). It is Haraam (prohibited) to deceive in Amaanat. Therefore if you had worked for lesser than the agreed hours, you should notify your employer. If he thereafter pays the full wage, that will be his kind gesture to you.

And Allah Knows Best

Muhammed Zakariyya Desai