Money & Budget

Monthly Budget Calculator

Enter your income and your usual monthly bills. The calculator adds up your spending, shows what is left, and turns that into a savings rate and a yearly figure so you can judge whether your budget is actually working.

What this calculator does

Adds up every monthly expense you list, subtracts the total from your income, and reports what is left as a monthly amount, a savings rate and a yearly projection. It is a snapshot of where your money goes right now, not a forecast.

How to interpret the result

Read the remaining amount first. If it is positive, the savings rate tells you how healthy it is: anything above 20% is comfortable, 10–20% is workable, and under 10% is thin. If it is negative, your listed spending already exceeds your income and the largest categories are where to look.

Assumptions

• Income and spending stay at the values you enter for the whole year.
• Take-home (after-tax) pay is used, so tax changes are not modelled.
• Irregular costs such as repairs or gifts are only counted if you put them in a field.

Limitations

• No inflation adjustment, so the yearly figure drifts from reality over time.
• Does not separate essential from optional spending, which matters when income drops.
• Cannot see subscriptions hidden inside "Other" — list them explicitly for an honest total.

How it works

Every expense you enter is summed into a single monthly spending figure. That total is subtracted from your income to give the amount remaining. The savings rate is the remaining amount divided by your income, expressed as a percentage, and the yearly figure simply multiplies the monthly remainder by twelve.

Worked example

On an income of 4,200 with 2,520 of listed expenses, 1,680 remains each month. That is a savings rate of 40% and roughly 20,160 across a full year, assuming income and spending stay level.

How to use it

1. Use take-home pay, not gross salary, so the result reflects money you can actually spend.
2. Pull the numbers from three months of statements and use the average rather than your best month.
3. Put annual bills such as insurance in the relevant field divided by twelve.
4. Press Calculate, then adjust a single category at a time to see how sensitive your margin is.

Factors to consider

• Irregular spending — car repairs, gifts, medical bills — is the most common reason a budget looks fine but fails.
• Variable income should be modelled on a low month, not an average one.
• Subscriptions belong in Other; they are small individually and rarely small together.

Useful for

• Checking whether your current spending pattern leaves room to save.
• Testing how a single change — a rent move, a cleared loan — shifts your margin.
• Building a realistic budget from three months of real statements before setting a savings target.

Frequently asked questions