The cost of a UK visa application is based on the type of visa you need to obtain in order to enter the UK
The United Kingdom Visas and Immigration authorities charge the applicants with a fee in Pounds Sterling (GBP) in order to cover the administration costs regarding handling of visa application.
Aside from Sterling, the fees can also be paid in local currency, according to the exchange rate set by the Home Office. All Home Office exchange rates are reviewed on a fortnightly basis and updated if they have changed beyond agreed tolerance of a 3-5% away from the commercial rate. The same Home Office exchange rate should be used by all posts for any given currency.