Property Value Calculator Formula

Understand the math behind the property value calculator. Each variable explained with a worked example.

Use the Property Value Calculator

Formulas Used

Estimated Property Value

estimated_value = base_value * (1 + condition_adjustment / 100)

Base Comparable Value

base_comp_value = base_value

Condition Adjustment Amount

adjustment_amount = base_value * condition_adjustment / 100

Variables

VariableDescriptionDefault
avg_comp_price_per_sqftAverage Comp Price/Sq Ft(USD)200
subject_sqftSubject Property Sq Ft(sq ft)2000
condition_adjustmentCondition Adjustment(%)0
base_valueDerived value= avg_comp_price_per_sqft * subject_sqftcalculated

How It Works

Property Value Estimation

This simplified comparable sales approach estimates property value using the average price per square foot of recently sold comparable homes, adjusted for condition.

Formula

Estimated Value = (Avg Comp $/Sq Ft x Subject Sq Ft) x (1 + Condition Adjustment%)

Notes

  • Gather at least 3 comparable sales within the past 6 months and 1 mile radius
  • Adjust for differences in condition, age, upgrades, and lot size
  • This provides a rough estimate; a professional appraisal is more precise

    • Worked Example

    Comparable homes sold at an average of $200 per sq ft. Your property is 2,000 sq ft in above-average condition (+5%).

    avg_comp_price_per_sqft = 200subject_sqft = 2000condition_adjustment = 5
    1. 01Base comparable value: $200 x 2,000 = $400,000
    2. 02Condition adjustment: $400,000 x 5% = $20,000
    3. 03Estimated property value: $400,000 + $20,000 = $420,000

    Frequently Asked Questions

    How accurate is this property value estimate?

    This provides a ballpark figure based on comparable sales data. Accuracy depends on how similar the comps are to your property. A licensed appraiser accounts for many more variables and produces a more reliable valuation.

    What makes a good comparable sale?

    Good comps are similar in size, age, style, condition, and location, and were sold recently (ideally within 3-6 months). The closer the match, the more reliable the estimate.

    What does the condition adjustment cover?

    The condition adjustment accounts for differences like updated kitchens, new roofs, better landscaping, or deferred maintenance compared to the comparable properties.

    Ready to run the numbers?

    Open Property Value Calculator