Start with annual cost, not a daily ticket
Multiply the full cost of an office day by the number of days you actually travel each year. Include fares or fuel, parking and any office-only spending. A £20 day becomes £2,820 a year at three days a week for 47 weeks.
Put a value on travel time
There is no universal price for an hour of your life. Some people can work or relax on a train; others lose time they would spend with family, exercising or sleeping. The calculator therefore lets you choose your own hourly value — including £0 for a cash-only view.
Compare post-tax salary, not gross salary
An extra £5,000 of gross salary is not £5,000 of extra spending money. Income Tax, National Insurance and, where relevant, student or postgraduate loan repayments reduce the amount that reaches your bank account. Pension arrangements can change the result again.
Include benefits and pension
A better employer pension, useful taxable benefits or a reliable bonus can compensate for some commuting disadvantage. Equally, a job with a higher salary but weaker pension and five office days can be worth less overall than it first appears.
A useful decision rule
Ask one question: “What gross salary would make me indifferent between these two jobs?” If the offer is below that break-even salary, you are effectively paying for the move through time, costs or weaker benefits. If it is comfortably above it, the move has a financial buffer.