Budgeting and spending · Calculator

Spending
audit.

Enter your monthly spending in each category. The tool estimates how much is recoverable with the tactics from Spending Less. Not a budget tracker. Just a 3-minute gut check on where the money is going and how much of it you can keep.

All math runs in your browser. Nothing sent to any server.

The question it answersHow much of my spending could I realistically cut?

Privacy: runs in your browser. What you enter stays on your device unless you copy a share link, which puts your inputs in the link.

Drag a slider or type the amount in the box; typed amounts above the slider range count in full. The savings range for each category is a rough site estimate based on the tactics on the Spending Less page, not a published figure. Your results will vary with current habits and local prices.

What this tool assumes
  • All amounts are monthly spending in today's dollars. A blank, negative or non-numeric entry counts as $0, and the box is set to 0 when you leave it, so a saved or shared result keeps the $0. There is no upper limit on typed amounts.
  • Each category's savings range is a rough site estimate, not a published figure or survey result: groceries 15 to 28%, household supplies 20 to 40%, personal care 25 to 45%, eating out and delivery 30 to 55%, coffee and drinks out 25 to 55%, subscriptions 30 to 55%, gas 5 to 15%.
  • The ~$X/month figure (and the yearly and 30-year figures built on it) is the midpoint of the low and high totals. Each category's potential saving is the midpoint of its own range, rounded to whole dollars so the rows add up to that monthly figure.
  • The 30-year figure assumes that midpoint is invested at the end of every month at a fixed 8% a year, compounded monthly. Inflation, taxes and fund fees are not modeled.

This is not a budget. This is an estimate of recoverable margin. Start with the category where the gap is largest.

HOW THIS IS CALCULATED

This tool runs entirely in your browser: no data is sent to any server.

  • Each category takes a monthly amount. The slider covers $0 to $1,500 for groceries, $800 for eating out, $500 for gas and $300 for the rest; the box next to it accepts any amount, and the box value is what the math uses (a blank, negative or non-numeric entry counts as $0, and the box is reset to 0 when you leave it). Each category carries a fixed savings range as a share of that amount: groceries 15 to 28%, household supplies 20 to 40%, personal care 25 to 45%, eating out and delivery 30 to 55%, coffee and drinks out 25 to 55%, subscriptions 30 to 55%, gas 5 to 15%.
  • The monthly total range = sum of the lows to sum of the highs, each rounded to the dollar. The midpoint of the unrounded totals, rounded to the dollar, is the ~$X/month figure; that × 12 is the yearly figure. Potential saving per category = the midpoint of its low and high saving, rounded to whole dollars by largest remainder so the rows add up exactly to the monthly figure (no row moves by more than $1).
  • Long-run figure = the monthly midpoint invested at the end of each month for 30 years at 8% a year, compounded monthly: saving × ((1 + 0.08 ÷ 12)360 − 1) ÷ (0.08 ÷ 12). With the default sliders, $306 a month comes to about $456,000.
  • "Where to start" names the category with the largest unrounded midpoint saving, when its displayed saving is above $10.

The savings ranges are rough site estimates based on the tactics on the Spending Less page, not published figures or survey data. The 8% return is a fixed assumption set by the page; for comparison, the S&P 500 with dividends compounded at about 10.0% a year before inflation from 1928 through 2025[1]. Inflation, taxes and fund fees are not modeled. Verify the methodology or inspect the source code in your browser's dev tools.

Where to go from here

Read next

Spend Less, Same Things

Groceries, household supplies, gas, subscriptions, personal care.

Explore further
  • How to Actually BudgetHow to actually budget: cover fixed costs, automate savings first, then spend the rest without guilt.
  • Lifestyle InflationWhen income rises, spending tends to rise with it. The mechanism, the math on $50K to $130K careers, and the half-and-half rule that breaks the pattern.
  • Budget BuilderEnter income and expenses to get a personalized budget with percentage breakdowns versus targets.
  • Opportunity Cost CalculatorShows what a one-time or recurring purchase could grow into over 10 to 40 years if invested instead, versus losing value to inflation as cash.

Sources

Bracketed numbers in the text link to these sources. Figures, rates and rules change: check each source’s date before acting on it.

  1. NYU Stern (Aswath Damodaran), Historical Returns on Stocks, Bonds and Bills: 1928-2024 (the table runs through 2025: $100 at the start of 1928 grew to $1,157,599 by the end of 2025). Checked 2026-09-26. ↩

Calculators are educational estimates, not financial advice. Disclosures · How pages are reviewed