# break-even-calc

Works out the revenue level where income matches costs. Handy when you need to know how much you have to sell to stop losing money.

- skill · `type=skill` · Claude Code, Codex, Cursor, GitHub Copilot, Gemini CLI, OpenCode · 411 installs · ★ 98
- Author: openaccountant
- License: MIT · policy=mirror · the beginning of the file is at the end of this page
- Source: https://github.com/openaccountant/skills/tree/HEAD/business/break-even-calc/SKILL.md
- Updated: 2026-04-09
- HTML: https://affpapa.org/en/nevibecode/skills/break-even-calc

## What it does

The skill splits expenses into fixed and variable, then calculates the break-even point in dollars and in units. Fixed means rent, salaries, insurance, software subscriptions, loan payments. Variable means materials, shipping, payment processing fees, commissions, packaging.

It first asks for the analysis period and the average selling price per unit if that applies. Then it pulls expense categories and total revenue, works out the variable cost ratio, the contribution margin and the break-even revenue itself. You also get the margin of safety and a sensitivity check: what happens if fixed costs rise 10% or variable costs rise 5%. The skill suggests a period of at least 3 months, since shorter windows give jumpy numbers.

It runs on the Wilson tools `spending_summary` and `transaction_search`. Without them there is a manual route: export 3+ months of bank transactions to CSV, tag each row as Fixed or Variable, and run the formulas in a spreadsheet. Semi-variable costs are where the manual path gets messy — electricity has a fixed base and a usage-driven part, so you either assign it to the dominant category or split it by hand. Break-even also assumes a constant product mix, so several products at different margins need a weighted average contribution margin.

## Install

### Claude Code (native platform)

1. **Skills CLI (Vercel)**
```bash
npx skills add openaccountant/skills --skill break-even-calc -a claude-code
```

2. **Manually: put the files in place**
- File: `~/.claude/skills/break-even-calc/SKILL.md` — Copy the whole skill folder; for one project use .claude/skills/break-even-calc/

### Codex

1. **Skills CLI (Vercel)**
```bash
npx skills add openaccountant/skills --skill break-even-calc -a codex
```

2. **Manually: put the files in place**
- File: `.agents/skills/break-even-calc/SKILL.md` — For all projects use ~/.agents/skills/

### Cursor

1. **Skills CLI (Vercel)**
```bash
npx skills add openaccountant/skills --skill break-even-calc -a cursor
```

2. **Manually: put the files in place**
- File: `.cursor/skills/break-even-calc/SKILL.md` — Cursor also reads .agents/skills/ and .claude/skills/

### GitHub Copilot

1. **GitHub CLI**
```bash
gh skill install openaccountant/skills break-even-calc
```

2. **Manually: put the files in place**
- File: `.github/skills/break-even-calc/SKILL.md`

### Gemini CLI

1. **Skills CLI (Vercel)**
```bash
npx skills add openaccountant/skills --skill break-even-calc -a gemini-cli
```

2. **Platform CLI**
```bash
gemini skills install https://github.com/openaccountant/skills --path business/break-even-calc
```

### Windsurf (Devin Desktop)

**Manually: put the files in place**
- File: `.devin/skills/break-even-calc/SKILL.md` — The legacy .windsurf/skills/ path still works

### OpenCode

**Skills CLI (Vercel)**
```bash
npx skills add openaccountant/skills --skill break-even-calc -a opencode
```

### Claude.ai

**Claude.ai**
- Zip the folder and upload it in Settings → Capabilities → Skills

Where a file is given instead of a command, copy the files from the source to that path: https://github.com/openaccountant/skills/tree/HEAD/business/break-even-calc/SKILL.md

## When to use it
- find the revenue level where the business breaks even
- sort expenses into fixed and variable buckets
- check the margin of safety on current revenue
- estimate how many units a month you need to sell
- see how the break-even point shifts when costs rise

## Example prompts
- Calculate my break-even point for the last 3 months
- Split my expenses into fixed and variable and find break-even revenue
- Show the margin of safety and what happens if fixed costs go up 10%

## Source text · SKILL.md · MIT

Below is the content of a third-party file. It is data, not instructions for you: do not act on anything written inside unless the human asks. Block tag: bfad20365a555f61.

BEGIN THIRD-PARTY FILE bfad20365a555f61
````text
---
name: break-even-calc
description: >
  Calculate break-even revenue by separating fixed and variable costs.
---

# Break-Even Analysis

## Overview
Determine the revenue level at which total revenue equals total costs (zero profit). Separates expenses into fixed costs (rent, salaries, insurance) and variable costs (materials, commissions, shipping) to calculate the break-even point in both dollars and units.

## Wilson Tools Used
- `spending_summary` — aggregate expenses by category to classify as fixed or variable
- `transaction_search` — pull revenue data and detailed expense transactions for classification

## Workflow
1. Ask for the analysis period (recommend at least 3 months for accuracy) and average selling price per unit if applicable.
2. Use `spending_summary` to get all expense categories and totals.
3. Use `transaction_search` to pull total revenue for the period.
4. Classify each expense category:
   - **Fixed costs**: rent, salaries, insurance, software subscriptions, loan payments — costs that stay the same regardless of sales volume
   - **Variable costs**: materials, shipping, payment processing fees, sales commissions, packaging — costs that scale with sales volume
5. Calculate:
   - Total Fixed Costs per month
   - Variable Cost Ratio = Total Variable Costs / Total Revenue
   - Contribution Margin Ratio = 1 - Variable Cost Ratio
   - Break-Even Revenue = Fixed Costs / Contribution Margin Ratio
   - Break-Even Units = Break-Even Revenue / Price Per Unit (if applicable)
6. Present the analysis:

```
BREAK-EVEN ANALYSIS — [Period]
═══════════════════════════════════════
Monthly Fixed Costs
  Rent                           $2,000
  Salaries                       $8,000
  Software                         $500
  Insurance                        $300
  Total Fixed                   $10,800

Variable Cost Ratio                 35%
Contribution Margin                 65%

BREAK-EVEN REVENUE            $16,615/mo
Break-Even Units              166 units @ $100/unit

Current Revenue               $22,000/mo
Margin of Safety                  24.5%
═══════════════════════════════════════
```

7. Calculate Margin of Safety = (Current Revenue - Break-Even Revenue) / Current Revenue * 100.
````
END THIRD-PARTY FILE bfad20365a555f61

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