This is what we found on Wikipedia regarding the Royal Palace Amsterdam (Koninklijk Paleis): Entry Ticket:

The following is a list of some of the largest buildings that are considered palaces in terms by area. The title of the "world's largest palace" is both difficult to award and controversial, as different countries use different standards to claim that their palace is the largest in the world.

The title of world's largest palace by area enclosed within the palace's fortified walls is held by China's Forbidden City complex in Beijing, which covers an area of 728,000 square metres (180 acres). The 980 buildings of the Forbidden City have a combined floor space of 1,614,600 square feet (150,001 m²) and contain 9,999 rooms (the ancient Chinese believed the god Yù Huáng had 10,000 rooms in his palace; so they constructed an earthly palace to have 9,999 and a half rooms, slightly fewer than in the divine palace, out of respect).

The world's largest official residence of a head of state is at the Kremlin Square at Moscow, Russian Federation. The Kremlin Square's earliest contemporary parts were made in 1159. The contemporary Terem palace building was made from 1839 to 1848, to serve as the Moscow residence to the tsar and his family. After the Russian Revolution 1917, it would also be used for meetings and conferences of the Supreme Soviet of the USSR and the residence for General secretary of the Soviet Union. It now has become the seat of president of the Russian Federation since the dissolution of the Soviet Union in 1991. The palace has five reception halls, out of them the Georgievsky Hall which is still used today for state and diplomatic receptions and official ceremonies; International treaties are signed within the Vladimirsky Hall, the Tsarina's Golden Chamber, the Terem Palace, and the Palace of Congresses are Aleksandrovsky are held at the Hall and Andreyevsky Hall were combined with forming the Kremlin as how it is today. The Grand Kremlin Palace by itself has an area of 25,000 square metres (270,000 sq ft), within triangular walls, which measures 2,235 meters in length with its walls having the thickness of 3.5 to 6.5 meters and 20 towers. The highest tower, Troitskaya, is around 80 meters in height with its proximity within the Kremlin Square. The palace measures 124 meters by 47 meters, the Terem palace had 9 churches and 700 rooms in the 3 storied building it adds up to the area of 28 hectares or 275,000 square metres (2,960,000 sq ft), as a 'city within a city' and therefore making it the biggest residential building for the head of state, in the world, when the Kremlin is also thereby included within the structure.

There is ongoing debate about the biggest palatial building and complex of the head of the state of a country, lies in differentiation between what is considerd a presidential complex and a singular palatial building estate, even some estimates indicate, if judging solely by a single building complex. The world's largest official residence of a head of state would be Rashtrapati Bhavan, New Delhi, Republic of India. This is the official residence of the President of India, located at the western end of Rajpath, Raisina Hill in New Delhi. The Presidential Estate is spread across 130 hectares of land area, which houses the main H-shaped building covering a massive 200,000 square metres (2,200,000 sq ft) of total floor area across 340 massive rooms and featuring a total of 2.50 kilometre long corridors. The entire structure was built using 700 million bricks and 3,000,000 cu ft (85,000 m3) of stone with little steel. The primary building sits in the centre of the estate, surrounded by multiple official buildings, massive yet beautiful gardens, lawns and large courtyards. Therefore, bigger than Grand Kremlin palace when compared on basis of building than entire palatial complex.

The world's largest private residence of a monarch is the Istana Nurul Iman in Brunei, with 200,000 square metres (2,200,000 sq ft) of floor space and contains 1,788 rooms. The building also has 257 bathrooms, a banqueting hall that can seat 5,000 guests, a garage that can fit 110 cars, five swimming pools, and an air-conditioned stable that can fit up to 200 polo ponies.

The Potala Palace in Lhasa, Tibet, with 1000 rooms on 13 levels, and over 130,000 square metres (1,400,000 sq ft) of floor space, is one of the largest palaces in the world by floor area. It was the winter residence of the Dalai Lama until 1959. (Many sources give the area as 360,000 square metres (3,900,000 sq ft).)

In the castle category, Prague and Malbork castles claim to be the world's largest. However, the task is made more difficult by the fact that castles underwent changes over centuries and were not originally intended to be palaces, but military strongholds, although most of the existing castles were either converted to palaces or a palace building was added to them. In addition to the difficulty of area measurement by floor area, land area and garden area, we are faced the question if the castle should be considered as it exists or in its historically most extended form. Prague castle is the biggest castle according to the Guinness Book of Records with area of 70,000 square metres (750,000 square feet), but this area does not contain the castle gardens, stables and Letohrádek Královny Anny located on a separate hill. Malbork Castle claims to be the biggest and bases this claim on the property lot size listed in UNESCO world heritage records with a lot size of 18.038 ha (44.57 acres).