Budget

Create budgets, track spending, and plan savings. For planning and awareness only—not tax or legal advice.

When to Use

• User wants to create or revise a budget
• User wants to track or categorize expenses
• User has a savings goal and wants a timeline or plan
• User asks how to allocate income (e.g. 50/30/20)
• User has income/expense data and wants a summary or breakdown

Workflow

1. Clarify scope: Monthly? Weekly? One-off project? What's the goal (spending control, savings target, debt payoff)?
2. Gather numbers: Income(s), fixed expenses, variable expenses, current savings, target amount or date
3. Choose format: Allocation rule (e.g. 50/30/20), category list, or custom
4. Build budget: Categories, amounts, and (if applicable) savings/debt line
5. Optional: Timeline to reach a goal, or "what if" (e.g. cut X to save Y by when)

Budget Frameworks

50/30/20

• 50% needs (housing, utilities, insurance, minimum debt, groceries, essentials)
• 30% wants (dining, entertainment, subscriptions, non-essential)
• 20% savings and debt payoff (above minimums)

Use when the user asks for "50/30/20" or a simple allocation. Compute from monthly gross or net income per user preference. For more frameworks, see references/frameworks.md.

Zero-Based (Every Dollar Has a Job)

• Income − All allocations = 0
• Categories: needs, wants, savings, debt, sinking funds
• No "leftover"; assign every dollar

Use when the user wants strict planning or "zero-based" budgeting.

Category / Envelope Style

• List categories (rent, food, transport, fun, savings, etc.)
• Set a cap per category per month
• Track spending per category (user provides or estimates)

Use when the user has a list of categories or wants to "envelope" by category.

Savings-First

• Set savings (and/or debt payoff) amount first
• Budget the rest for expenses
• Formula: Income − Savings = Spending allowance

Use when the user's main goal is hitting a savings target.

Output Format

# Budget: [Title — e.g. Monthly 2025]

## Summary

[Income, total planned spending, planned savings, and one-line takeaway.]

## Income

| Source   | Amount   |
| -------- | -------- |
| [Source] | [Amount] |

## Planned Spending

### Needs (or Fixed)

| Category   | Amount   |
| ---------- | -------- |
| [Category] | [Amount] |

### Wants (or Variable)

| Category   | Amount   |
| ---------- | -------- |
| [Category] | [Amount] |

### Savings & Debt

| Category       | Amount   |
| -------------- | -------- |
| [Savings/Debt] | [Amount] |

## Totals

- Income: [total]
- Planned spending: [total]
- Planned savings: [total]
- Difference: [surplus/deficit]

## [Optional] Savings Goal

- Target: [amount]
- Monthly to save: [amount]
- At this rate: [time to goal] (assuming no change)

Savings Goals

When the user has a target amount or date:

• Target + date → Required monthly (or weekly) savings = Target / Months (or weeks) to date
• Target + monthly amount → Time to goal = Target / Monthly amount (in months)
• Current + monthly + rate → Simple projection: "In N months you'd have about X" (no interest or inflation unless user asks; state assumptions)

Always state assumptions (e.g. no interest, no tax, nominal amounts).

Tracking Expenses

When the user wants to track or categorize spending:

• Categories: Use their list or suggest a simple set (housing, food, transport, utilities, insurance, discretionary, savings, debt).
• Format: Table or list with category and amount; optional percentage of income.
• If they provide a list: Map items to categories and sum; show breakdown and total.

Don't invent transactions; use only what the user provides.

Time Scope

• Monthly is the default for personal budgets unless the user says weekly, annual, or one-off.
• Annual: Multiply monthly by 12 or use annual income/expenses if that's what they give.
• State the period clearly (e.g. "Monthly budget" or "January–December 2025").

Caveats

• Round to sensible precision (e.g. whole dollars for budgets).
• State if numbers are gross vs net, and currency.
• Remind that this is for planning; tax or legal questions need a professional.

Anti-Patterns

• ❌ Making up income or expenses; use only user-provided or clearly estimated values
• ❌ Guaranteeing outcomes (e.g. "you will reach your goal by X")
• ❌ Giving tax or legal advice; point to a professional when relevant
• ❌ Unclear time period (monthly vs annual) or currency