Doctors will use a new programme to give patients their percentage chance of having cancer based on their including age, weight and symptoms such as bleeding or constant tiredness.
Patients calculated to be at high risk of cancer developing would be referred for urgent tests in hospital within two weeks.
The plan was unveiled by Professor Mike Richards, the Govenment's cancer czar, in a bid to prevent the 10,000 unnecessary deaths each year caused by late diagnosis.
Every GP in England could be using the software within five years, he said.
Cancer is the UK's biggest killer after heart disease and strokes and kills more than 150,000 people every year, around half of those diagnosed.
England is the first country to use the tool, as it has a lower rate of early cancer diagnosis than many European countries, Professor Richards added.
GPs spot cancer in 90 per cent of patients with screening picking up the other ten per cent.
Although some patients do not seek help in time, many cancers become fatal because they are not diagnosed by doctors at an early stage. There are more than 200 forms of cancer and the early stages can be similar to the symptoms of other conditions.