The tool will quickly show the level of mid-term contract rises imposed by the major providers.
Figures from the Office for National Statistics reveal that households will see an average rise of £11.25 per month after the inflation-busting 14.4 percent price hike some, including BT, are applying in April.
Many broadband providers are hiking their charges by the rate of inflation plus 3.9 percent on top in the middle of contracts, without giving the customer the right to exit the contract.
The free calculator has been developed by Hyperoptic, the full fibre broadband provider which has never used mid-contract price rises.
Six in ten people are unaware that their monthly charge
for their broadband contract will change, according to research.
Hyperoptic’s Lutfu Kitapci said: “It’s unfair and misleading to let customers sign up to a contract price, only to increase that price months later – especially given the cost-of-living crisis when everyone is trying to budget.
“This is the last thing people need to contend with in these financially difficult times. Our free calculator will allow people to find out exactly what extra charges they will be hit with from April onwards, so that they can plan for that – and choose a different provider when their contract expires.”