Bitcoins do not have value as a physical commodity like gold and are not widely accepted as legal tender like dollars.
Rather, Bitcoin appears to have value for the following reasons: It is popular.
In short, people accept and trade in Bitcoin because other people accept and trade in Bitcoin.
the value does not been decided by anyone for Bitcoin it can be anything that demand or its popularity will made the value more higher but the most important thing is people will accept it for their future that's why the value of Bitcoin will be decided and increasing every time.