Free budget calculators
Three small tools we built because we needed them ourselves. They run entirely in your browser — no account, no uploads, nothing saved — and each one answers a question a static budget sheet cannot.
Cumulative budget calculator
Carry every month forward — including annual bills — and see the exact month your running balance would hit zero.
50/30/20 calculator
Split your take-home pay into needs, wants and savings, and compare the targets with what you actually spend.
Emergency fund calculator
Size your fund on essential costs, see how many months you are covered for today, and get the date it is complete.
Want the same numbers kept up to date?
Calculators work on figures you type once. The Cumulative Budget app keeps the projection alive from your real income and expenses, on web and Android, with shared accounts for households.
Guides
Every calculator has a longer explainer behind it in our budgeting guides.