The formula
How it works
Split your monthly income into needs, wants and savings using the popular 50/30/20 rule — or your own percentages. It turns a single pay figure into clear spending targets you can actually budget against.
FAQ
What is the 50/30/20 rule?
A simple budgeting guide: spend about 50% of your take-home pay on needs, 30% on wants, and put 20% toward savings and debt. It is a starting point you can adjust to your situation.
Should I use gross or take-home pay?
Use take-home (after-tax) pay, since that is the money you actually control. Budgeting from your gross salary overstates what you have to spend.
What counts as a need versus a want?
Needs are costs you must pay to live and work — rent, groceries, utilities, minimum debt payments. Wants are anything optional, like dining out, streaming subscriptions or hobbies, even if they feel routine.
What if my needs already cost more than 50% of my income?
That is common in high cost-of-living areas — you can shift the split, for example to 60/20/20, and still keep the same three-bucket structure. The goal is a workable plan for your numbers, not rigid adherence to 50/30/20.
How do I budget with irregular income?
Base your percentages on your lowest typical month so essentials are always covered, then treat income above that as a bonus to split across the same three buckets. Building a buffer in months you earn more smooths out the leaner ones.
Does debt repayment go in needs or savings?
Minimum payments on debt are a need, since missing them has real consequences. Extra payments beyond the minimum are usually counted with savings, since they build financial position just like putting money aside.
How often should I revisit my budget split?
Check it whenever your income or major expenses change, and otherwise review it every few months to make sure the percentages still match how you actually spend. A budget that is never adjusted tends to drift out of date.
About the budget calculator
This calculator splits your monthly income into three buckets — needs, wants and savings — so you can see exactly how much to put toward each. It is based on the 50/30/20 rule, a widely used guideline that keeps budgeting simple: cover your essentials, allow some room for enjoyment, and consistently save. Turning one income figure into three concrete amounts is often all it takes to bring spending under control.
How to use it
Enter your monthly take-home pay — the amount that actually lands in your account after tax. The default splits it 50% needs, 30% wants and 20% savings, but you can change the needs and wants percentages and the savings share adjusts to make 100%. For example, on $3,000 a month the 50/30/20 rule gives $1,500 for needs, $900 for wants and $600 for savings. Adjust the shares to fit your own priorities.
The formula
The rule simply divides income by percentage, keeping the three shares adding to 100%: . Each amount is your income times its share — needs are income under the standard rule, and so on. The savings share is whatever remains after needs and wants, so raising one of the others automatically shrinks the amount you save.
Where it is used
The 50/30/20 split is a go-to for personal budgeting, taught by financial advisers and built into many money apps because it is easy to remember and flexible. People use it to check whether their rent or lifestyle is eating too much of their pay, to set a savings target, and to plan around a change in income. It works as a first budget for beginners and a quick sanity check for everyone else.