Budget Calculator
Build your monthly budget, track spending by category, and see your savings rate
Results & Details
// 50 / 30 / 20 Rule
// Expense Breakdown
// Annual Projection
How to Use the Budget Calculator
Enter your income sources and monthly expenses across three categories — Needs, Wants, and Savings — to build a complete picture of your finances. The calculator compares your budget to the 50/30/20 rule and shows your savings rate, leftover money, and annual projection.
The 50/30/20 Rule
Popularised by US Senator Elizabeth Warren, the 50/30/20 rule is a simple budgeting framework. Spend no more than 50% of take-home pay on needs (rent, food, utilities, transport), no more than 30% on wants (dining out, entertainment, hobbies), and save or put at least 20% toward savings and debt repayment.
Needs vs Wants
Needs are expenses you cannot avoid — housing, groceries, utility bills, minimum debt payments, insurance, and essential transport. Wants are lifestyle choices — restaurants, streaming services, gym memberships, holidays, and non-essential shopping. The line between needs and wants is personal and context-dependent.
What Savings Rate Should I Target?
A 20% savings rate is a solid general target. Financial independence enthusiasts often target 40–60% or more to retire early. If 20% is not currently achievable, start with whatever you can and increase it gradually. Even a 5% savings rate compounds significantly over decades.
Budgeting Methods That Actually Survive Contact With Real Life
Built and verified by Andrius R. · Updated June 2026
Most budgets fail the same way: too detailed to maintain, too rigid to absorb a surprise, abandoned by February. The fix isn't more discipline — it's picking a method whose maintenance cost matches your patience. Here are the main ones, honestly compared.
The 50/30/20 rule, worked through
| Bucket | Share | Amount | What goes here |
|---|---|---|---|
| Needs | 50% | $1,750 | Rent/mortgage, utilities, groceries, insurance, minimum debt payments, transport to work |
| Wants | 30% | $1,050 | Dining out, streaming, hobbies, travel, upgrades of any need |
| Savings & debt | 20% | $700 | Emergency fund, retirement, extra debt payments beyond minimums |
The hard part is honest sorting: groceries are a need, the premium version of them is partly a want; a car payment is a need, the size of it may not be. The rule's real value is the 20% floor — it makes saving a budget line instead of a leftover.
When 50/30/20 doesn't fit (and what to do)
In high-cost cities, housing alone can eat 40%+ of net income, making the 50% needs cap arithmetic fantasy. Don't abandon the framework — rebalance it: 60/20/20 keeps the savings floor intact while admitting reality, and 70/20/10 is a legitimate starting point when money is tight. The non-negotiable is keeping some automatic savings percentage, even 5%; the ratio between needs and wants can flex. On the other end, high earners should outgrow the rule — someone netting $10k/month has no business capping savings at 20% just because a rule of thumb said so.
The other methods, and who each suits
- Zero-based budgeting: assign every dollar a job until income minus allocations equals zero. Maximum control and awareness; maximum maintenance. Best for tight budgets, debt payoff sprints, or anyone who finds money "evaporating."
- Pay-yourself-first: automate savings and fixed bills on payday, spend the remainder guilt-free with no categories at all. Minimum effort; best for people with stable incomes and reasonable habits who hate tracking. Arguably the highest success rate per unit of willpower.
- Envelope/cash-stuffing: physical or digital envelopes per category; when one's empty, that spending stops. Crude but behaviorally powerful for chronic over-spenders — the spending limit is enforced by reality, not memory.
All four methods reduce to the same equation — income − outgo ≥ 0 with savings protected. Choose by personality, not by what worked for someone on the internet.
The two failure modes to design against
- Forgetting non-monthly costs. Car insurance, holidays, annual subscriptions, birthdays — irregular expenses are where "good" budgets die. Sum the yearly total, divide by 12, and treat that as a monthly bill into a separate buffer ("sinking fund"). A budget without this line isn't conservative, it's fictional.
- Zero slack. A budget allocating 100% perfectly breaks on the first surprise and the demoralization spreads. Leave a small unassigned miscellaneous line; its job is to absorb chaos so the rest of the budget survives.
Track for one month before optimizing anything — most people misestimate at least one category by 50%, and a budget built on guessed numbers optimizes the wrong things. Then connect the 20% to its destinations: an emergency fund first, then debt and investing — the full ordering is in our savings guide.
From the Blog
// Pay Yourself First
Transfer savings automatically on payday before spending anything. Treat it like a non-negotiable bill.
// Track Every Month
Review your budget at month end. Consistent tracking is more important than having a perfect budget from day one.
// Emergency Fund First
Before investing, build 3–6 months of expenses as an emergency fund. This prevents debt when life happens.
// Small Cuts Add Up
Cancelling £10 of unused subscriptions and saving that extra each month compounds to over £1,500 in 10 years.