2 tools

Everyday Money

The small calculations that come up constantly, done properly — including the ones people most often get backwards, like percentage increase versus percentage of a total.

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Budget Calculator

Sort a month of take-home pay into needs, wants and saving, see the three shares it actually produces, and compare them against the 50/30/20 framework and what US households measurably spend.

This adds up a month of spending in three groups and divides each by your take-home pay, which turns a list of amounts into three percentages you can compare against something. The needs group is what you would struggle to stop paying: housing, transport, food at home, insurance and the contractual minimum on any debt. Wants is everything discretionary, entered as one total. Saving is money you deliberately move somewhere — into savings, into a retirement account, or onto debt above the minimum. It reports the three shares, the gap between each share and the 50/30/20 framework in dollars rather than in percentage points, and whatever is left unallocated. That last figure is kept separate on purpose: money not yet assigned to anything is not saved, and adding it to the savings line would report a household as saving 20% when it is saving 12% and losing the rest to whatever comes up.

Open the budget calculator

Also in everyday money

Each one answers a different question, not a rephrasing of the same one.

Emergency Fund Calculator Work out what a cash reserve of the size you choose actually costs, how much of it you already have, and how long the rest takes at the amount you can genuinely put aside.

Answered here

Questions these tools actually answer.

Each links to the tool that answers it, where the full explanation sits beside the calculation.