50/30/20 budget calculator

The 50/30/20 rule splits your take-home pay three ways: half to needs, a third to wants, a fifth to savings and debt. It comes from Elizabeth Warren and Amelia Warren Tyagi's book All Your Worth, and it has lasted because it is simple enough to actually follow.

Put your monthly take-home pay in and you will see the three numbers. The percentages are editable, because the standard split does not survive contact with every city or every income.

What actually counts as a need

This is where most people get the split wrong. A need is something you cannot stop paying without a real consequence: rent, groceries, utilities, transport to work, insurance, and the minimum payment on any debt. Not the nice version of those things.

Your phone bill is a need. The upgrade plan on the newest handset is a want. Groceries are a need; the weekly restaurant meal is a want. Move one borderline item into needs and the whole budget stops meaning anything, because "needs" quietly becomes "everything I already spend".

When 50/30/20 doesn't fit

On a low income, or in an expensive city, needs alone can exceed 50% and no amount of rearranging fixes that. The rule is not a moral test. Use the editable percentages above and aim for something honest: 70/20/10 that you actually hit beats 50/30/20 that you abandon in March.

The reverse applies too. On a high income, holding wants at 30% is often just spending money because a percentage said you could. If needs are 25% of your pay, save the difference rather than inflating the middle bucket.

The part that makes it work

A budget only does something if you know where you actually landed at the end of the month, and that is the step people skip. Splitting the pay is five minutes; tracking against it is the habit. If logging a purchase takes more than a few seconds you will stop, which is why a ledger that files entries as you type them matters more than the sophistication of the budget itself.