50/30/20 Rule Calculator
Enter your net salary and see how much should go to needs, wants, and savings -- with whatever percentages you want, not just the classic ones.
How we calculated this
Each bucket = net salary × its percentage. By definition, 50% + 30% + 20% = your whole salary -- if you adjust the percentages, the same principle applies to the new split.
What goes in each bucket
Needs are what you have to pay regardless of whether you want to: rent or mortgage, water, electricity and internet bills, basic groceries, transport to work, mandatory insurance. If you stopped paying them, you'd have a real problem, not just an inconvenience. Wants are everything you choose to spend by choice, not obligation: eating out, streaming subscriptions, clothing beyond the essentials, nights out, hobbies. The line between need and want is personal to some extent -- a car can be a need for someone who lives far from work and a want for someone with public transport at the door. Savings include your emergency fund, retirement contributions, specific goals, and any amount paid toward debt above the required minimum.
Why the rule breaks down in expensive cities
The 50/30/20 rule was born in the United States, in a context where average rent is a much smaller share of income than in many parts of Lisbon or Porto today. If your rent alone already eats up 45% or 50% of your net salary, there's little or nothing left for the rest of your needs, and the classic rule stops being realistic. That doesn't mean you're managing money badly -- it means the rule's starting point doesn't match your market reality. In those cases, it makes more sense to use a split like 60/20/20 or 65/15/20, always keeping a deliberate slice for savings, even if small.
How to adapt the percentages to your life
There's nothing wrong with adjusting the three numbers, as long as they still add up to 100% of your income. What matters is keeping the discipline of having a defined slice for savings -- even if it's 10% instead of 20% during some periods of your life -- instead of letting savings be "whatever happens to be left over" at the end of the month, which tends to be zero.
What this calculator doesn't do
It doesn't categorise your actual expenses for you, and it doesn't know whether you're spending more on wants than you think. It's a starting point for splitting your income into three slices -- the work of seeing where your money is actually going is still yours.
Frequently asked questions
What goes in each bucket?
Needs (50%): rent or mortgage, bills, groceries, transport, insurance -- what you have to pay whether you like it or not. Wants (30%): eating out, subscriptions, leisure, non-essential clothing -- what you choose to spend, not what you're obligated to pay. Savings (20%): your emergency fund, retirement, goals, and any debt payment above the minimum.
What if rent alone already goes over 50%?
That's common in expensive cities -- Lisbon and Porto included -- and it doesn't mean you're doing anything wrong. Adjust the percentages to your reality, for example 60/20/20 or 65/15/20, instead of forcing 50% somewhere that's rarely realistic. What matters is keeping savings as a deliberate slice, even if small, not zero.
Does the 50/30/20 rule use gross or net income?
Net -- what you actually take home after tax and social security, and what you can actually spend or save. That's the number to use in this calculator.
Related tools
You know the three numbers. Now they need following, every month.
In Otterbond you create budget categories with a monthly amount each, for example needs, wants and savings, and it tracks what you spend against them.
Try it freeEstimates based on general personal-finance rules, not financial, legal or tax advice.