The calculator lets you figure out what your monthly cash allowance will be on the day you turn up to work.
It will tell you how much you’ll be paid and where you’ll live in your salary packet.
We use it every week to calculate how much money we have left for rent, bills, car payments and gym memberships.
But there’s a big catch.
It only works on the first two days of your pay period, so you can’t use it to figure your total income for the week before your pay day.
This is because you’ll need to work through the pay period on a day or two earlier than the rest of the week.
So you’ll have to work your way through the week, or spend it on things you can get done on the weekend.
This calculator can’t figure out the amount of money you can earn over the whole week.
We also had to tweak the calculator so that it can work out how much cash you’re actually earning.
The basic method is to find the number of days your pay will be paid on the Friday of the fortnight and subtract that from your actual salary packet, so that the calculator calculates a weekly sum of how much your weekly cash is.
If you’re paying your rent on Friday, subtract the weekly rent from your salary.
If not, subtract it from the pay packet.
Then multiply the result by 4.
This gives you your monthly amount of income.
For example, if your monthly rent is £8,000 and your monthly pay packet is £6,000, the calculator will give you £12,000 in income for each week.
But the calculator doesn’t figure how much of that income comes from rent and how much comes from bills.
This means you’ll likely have to pay extra taxes or bills.
A further tweak is to include a range of items.
For instance, we used the following two items to calculate the amount that you can expect to earn over a full week: food and drink, and childcare.
To work out your weekly income, you’ll use the calculator to divide the sum of all the items in your weekly pay packet by the number you’re expecting to earn.
For each week you earn less than the expected income, it’s calculated as £4 less than your expected weekly pay.
For more information on calculating your weekly wage, see the calculator’s instructions.
Read more: What you need to know about pay rise rules