Updated · Methodology: named formula library
Home Office Deduction Calculator
Calculate the IRS home office deduction (simplified $5/sq ft method).
Sq Ft to Rate = 30:1 (30 as decimal).
Home Office Deduction
Simplified method: $5/sq ft up to 300 sq ft = $1,500 max. Regular method: actual expenses × business-use %. Regular often higher but requires tracking.
Worked Example
150 Sq Ft to 5 Rate
- a
- 150
- b
- 5
- Result
- 30:1 (30.00)
150 / 5 = 30.00. Simplified: 30:1.
When to Use This Calculator
- Maximize self-employed deductions
Limitations & Common Mistakes
- Results are estimates from your inputs.
- Verify with current data for major decisions.
Frequently Asked Questions
How is the Home Office Deduction Calculator computed?
Sq Ft divided by Rate, plus a simplified ratio (e.g., 4:3) using greatest common divisor. Both decimal and ratio forms are useful in different contexts: decimal for math, ratio form for comparisons or recipe scaling.
What does Sq Ft:Rate mean?
It's a comparison: for every Rate unit, you have a corresponding amount of Sq Ft. Useful when the absolute numbers matter less than the proportion (e.g., reading 8:1 LTV/CAC immediately tells you the unit economics are healthy without needing the dollar amounts).
Why simplify the ratio?
4:3 is more readable than 200:150. The simplified form (using greatest common divisor) preserves the proportion while making it easier to interpret. Common simplified ratios: 16:9 (widescreen), 4:3 (legacy displays), 3:1 (LTV:CAC for SaaS).
When is a ratio more useful than the absolute values?
Comparison across scales. A $1B company and a $1M company can both have a 3:1 LTV:CAC; the ratio reveals comparable unit economics regardless of scale. Use ratios for benchmarking; use absolute numbers for budgeting.
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