How much is a worldwide patent?

There is no such thing as a worldwide patent. Each country has its own patent laws, and ultimately each country has to make its own decision as to whether it will grant a patent. There are some international arrangements (eg the Patent Cooperation Treaty, the European Patent Convention) which help by carrying out some of the patent examining functions centrally and these can help in reducing the costs?

To obtain a granted patent in, say, UK, USA, Germany, France, Spain, Italy, Netherlands, Sweden and Japan is likely to cost between £30,000 and £50,000. This cost is spread over a period of about 6 years.