Monthly budget breakdown

Build a clear monthly spending plan from your income and expenses, with realistic category targets and trade-offs.

Change note: Initial version

Prompt

Help me build a monthly budget. I want practical budgeting, not investment advice.

My situation:
- Monthly take-home income: {{income}}
- Currency and region: {{currency}}
- Fixed monthly costs (rent, utilities, insurance, debt payments, subscriptions): {{fixed}}
- Typical variable spending (food, transport, fun, shopping, etc.): {{variable}}
- Goal for the next 6 months: {{goal}}
- Preferred method: {{method}}

Do the following:
1. Total my spending, show the monthly surplus or shortfall, and say clearly if the numbers I gave do not add up or look incomplete.
2. Propose a category-by-category monthly plan with amounts and percentage of income, following my preferred method where it fits my situation.
3. Point out the three categories where trimming would hurt least, with a specific amount to cut for each.
4. Show how fast I would reach my goal under the plan, and one faster and one slower scenario.
5. Give me a simple weekly check-in routine that takes under 10 minutes.

Format: a markdown table for the plan, then short bullet lists for the rest. Show your arithmetic so I can verify it. Do not recommend specific investments, financial products or tax strategies. Add one line reminding me this is general budgeting guidance, not financial advice, and that a licensed professional can help with debt, tax or investing decisions.

Variables

• {{income}}Monthly take-home incometext

  Default: $4,200

• {{currency}}Currency and regiontext

  Default: USD, United States

• {{fixed}}Fixed monthly costslong

  Default: Rent $1,500; utilities $180; car insurance $110; phone $55; student loan $240; streaming and apps $45

• {{variable}}Typical variable spendinglong

  Default: Groceries about $450; eating out about $300; gas $120; shopping $150; misc $100

• {{goal}}Goaltext

  Default: Build a $5,000 emergency fund

• {{method}}Budget methodselect

  Options: 50/30/20, Zero-based, Pay-yourself-first, Envelope-style, No preference

  Default: 50/30/20

Example output

**Check the numbers:** Fixed costs total $2,130. Variable spending totals $1,120. Combined $3,250 against $4,200 income, so you have a $950 monthly surplus, which suggests some spending is untracked (annual fees, gifts, medical) so I added a buffer.

| Category | Amount | % of income |
|---|---|---|
| Needs (rent, utilities, insurance, phone, loan, groceries, gas) | $2,655 | 63% |
| Wants (eating out, shopping, subscriptions) | $595 | 14% |
| Irregular costs buffer | $150 | 4% |
| Emergency fund | $800 | 19% |

**Easiest trims:** eating out -$75, shopping -$40, subscriptions -$15 (audit what you use).

**Goal timeline:** $800/month reaches $5,000 in about 6.3 months. Faster: $1,000/month, 5 months. Slower: $600/month, 8.3 months.

**Weekly check-in (10 min):** compare spending to the plan, move leftover money to savings, adjust one category.

This is general budgeting guidance, not financial advice.

Notes

Asking the model to sanity-check your numbers first catches the untracked spending that sinks most budgets. Paste a month of bank transactions as the variable spending for sharper categories.