Is a water buffalo bigger than tiger?

Yes, a water buffalo is generally bigger than a tiger.

* Water Buffalo: An adult male water buffalo can weigh between 900-1200 kg (2000-2600 lbs) and stand up to 1.8 meters (6 ft) tall at the shoulder.

* Tiger: The largest tiger subspecies, the Siberian tiger, can weigh up to 300 kg (660 lbs) and stand up to 1.1 meters (3.6 ft) tall at the shoulder.

So, even the largest tiger is significantly smaller than a fully grown water buffalo.