# Vacancy Rate Calculator

> Calculate a property’s vacancy rate by vacant units, by vacant unit-days over a period, or economically by rent lost, with occupancy and rent lost.

Category: Real estate · Applies to: Worldwide · Last updated: 2026-10-29
Interactive calculator: https://calculators.geekmidst.com/calculators/vacancy-rate-calculator

Vacancy can be measured three ways: the share of units empty today, the share of unit-days empty over a period, or the share of potential rent not collected. Each answers a different question.

Also called: Occupancy rate calculator, Economic vacancy calculator.

## Inputs
- Measure vacancy by (options: Vacant units today (physical), Vacant unit-days over a period, Rent lost (economic); default units)
- Total units (default 20)
- Vacant units (default 2)
- Vacant unit-days in the period (default 146)
- Days in the period (default 365)
- Market rent per unit (per month) (default 1500; optional)
- Gross potential rent (default 100000)
- Rent actually collected (default 92000)
- Currency

## Results
- Vacancy rate
- Occupancy rate
- Rent lost to vacancy

## Formula

```
Physical = Vacant units ÷ Total units;  Time-based = Vacant unit-days ÷ (Units × Days);  Economic = (Potential rent − Collected rent) ÷ Potential rent;  Occupancy = 1 − Vacancy
```

Where:
- Vacant unit-days: the sum of empty days across all units
- Potential rent: rent at market rates with every unit let for the whole period

## Worked example
1. Vacancy = 2 ÷ 20 = 10%; occupancy = 90%.
2. Rent lost each month = 2 × 1,500 = 3,000.

**Result:** With 2 of 20 units empty, physical vacancy is 10% and the building loses 3,000 of rent a month.

## What the result means

Economic vacancy is usually higher than physical vacancy because it also captures concessions, discounts and unpaid rent. Use it in income forecasts; use physical vacancy to track leasing activity.

## Assumptions and limits
- For the units method, rent lost is monthly; for unit-days it is for the period, at 12 months’ rent ÷ 365 per day.
- Units of different sizes and rents are treated alike in the physical and unit-days methods.

## Questions

### Which vacancy rate should I use in a pro forma?

An economic vacancy and credit-loss allowance, based on the property’s history or local market data, because that is what reduces income.

### Is a unit under renovation vacant?

For physical vacancy, yes. Some owners report it separately as “down” units; be consistent across periods.

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- [Rent Collection Rate Calculator](https://calculators.geekmidst.com/calculators/rent-collection-rate-calculator)
- [Cap Rate Calculator](https://calculators.geekmidst.com/calculators/capitalization-rate-calculator)
- [Percentage Calculator](https://calculators.geekmidst.com/calculators/percentage-calculator)

Source: GM¹X CalcVerse — https://calculators.geekmidst.com/calculators/vacancy-rate-calculator