Free Real Estate & Measurement Tools
Practical calculators for appraisers, homeowners, and anyone who needs to measure. No account required.
Floor Plan Square Footage Calculator
Most popularAdd rooms by length × width and get a running total instantly. Supports feet and inches. Useful for quick GLA estimates before measuring.
Floor Plan Scale Calculator
Convert measurements on a scaled floor plan to real dimensions. Supports imperial (1/4" = 1'-0") and metric ratio (1:50, 1:100, 1:200) scales.
GLA Calculator
Select a space type (basement, attic, garage, sunroom, etc.) and get an instant ANSI Z765 ruling. Counts as GLA, excluded, or depends on conditions.
Appraisal Adjustment Calculator
Enter subject GLA, comp GLA, and your dollar-per-sqft adjustment rate. Outputs the exact dollar adjustment with the math shown.
Price Per Square Foot Calculator
Two modes: find the $/sqft of a property, or find a home's value from its size and local rate. Includes U.S. benchmark data by region.
Impervious Surface Calculator
Calculate lot coverage percentage and remaining impervious allowance. Enter house footprint, driveway, patio, and other hard surfaces to check against your zoning limit.
Effective Age Calculator
Estimate a property's effective age based on UAD condition rating (C1-C6) and major updates completed in the last 15 years. Outputs effective age, remaining economic life, and depreciation %.
Remaining Economic Life Calculator
Calculate remaining economic life and physical depreciation for cost approach appraisals. Enter effective age, total economic life, and optional replacement cost new.
UAD Condition and Quality Adjustment Calculator
Estimate dollar adjustments for condition (C1-C6) and quality (Q1-Q6) differences between the subject property and comparable sales, calibrated to your value range.
ANSI Square Footage Calculator
Add rooms by name, length, width, and floor level to calculate GLA per ANSI Z765-2021 standards. Below-grade areas shown separately and excluded from GLA.
Paired Sales Analysis Calculator
Isolate the market value of a single feature by comparing two matched sales. Adjusts for GLA differences and shows a full step-by-step calculation.
Cost Approach Appraisal Calculator
Estimate property value using site value plus depreciated cost of improvements. Calculates physical depreciation, functional and external obsolescence, and indicated value.
Absorption Rate Calculator
Calculate monthly absorption rate and months of supply from sales volume and active listings. Shows market condition label from strong seller's market to strong buyer's market.
Income Approach Calculator
Estimate property value via direct capitalization. Enter monthly rent, vacancy, operating expenses, and cap rate to get NOI, indicated value, and GRM.
Gross Rent Multiplier Calculator
Two modes: find property value from rent and GRM, or calculate GRM from price and rent. Includes market context for interpreting the result.
Cubic Footage Calculator
NewCalculate cubic footage from length, width, and height. Converts to cubic yards, cubic meters, gallons, and liters.
Square Feet to Square Meters Converter
NewConvert between square feet and square meters instantly. Includes a reference table for common home sizes.
Volume Calculator
NewCalculate room volume in cubic feet, cubic meters, gallons, and liters. Supports rectangular rooms and cylinders.
Acreage Calculator
NewConvert square feet to acres, calculate acreage from dimensions, or convert acres back to square feet. Common lot size reference included.
Square Feet to Square Yards Calculator
NewConvert between square feet and square yards. 1 sq yd = 9 sq ft. Reference table for common room sizes.
Inches to Square Feet Calculator
NewConvert square inches to square feet, or enter length and width in inches to get square footage.
Surface Area Calculator
NewCalculate total interior surface area of a room including walls, floor, and ceiling. Subtract doors and windows for paint estimates.
Feet to Square Feet Calculator
NewEnter length and width in feet to calculate square footage. Reference table with common room dimensions.
Wall Square Footage Calculator
NewCalculate wall area for any room. Subtract doors and windows for accurate paint, wallpaper, or drywall estimates.
Irregular Shape Area Calculator
NewCalculate square footage for L-shaped rooms and irregular floor plans by breaking them into rectangular sections.
Perimeter Calculator
NewCalculate the perimeter of rectangles, squares, and L-shaped rooms. Great for fencing, baseboards, and trim estimates.
Land Area Calculator
NewCalculate lot area in square feet, acres, square meters, and hectares. Supports rectangular and irregular 4-sided lots.
Exterior Square Footage Calculator
NewCalculate exterior wall area for siding, paint, and stucco. Subtract windows and doors for accurate material estimates.
Ceiling Square Footage Calculator
NewCalculate ceiling area for flat and vaulted ceilings. Add multiple rooms for whole-house estimates.
Need to measure an actual floor plan?
PlanSnapper lets you sketch or upload a floor plan and measure square footage with professional accuracy: the same way appraisers do it.
Try PlanSnapper free →Related guides
About these tools
These calculators are built for real estate appraisers, agents, and homeowners who need quick answers without pulling up a full floor plan measurement session. They're based on ANSI Z765 standards: the same methodology used in professional residential appraisals.
All tools run in your browser. No data is sent to our servers. Results are for estimation purposes: for a certified appraisal, consult a licensed appraiser.
Frequently Asked Questions
Are these tools really free?
Yes, all calculators on this page are free with no signup required. They run entirely in your browser. The paid product is the floor plan upload tool at /go (a $9 day pass for full access).
Which calculator should I use to find my home's square footage?
If you have a floor plan, use the floor plan square footage calculator. If you only have room dimensions, use the GLA calculator or the irregular shape area calculator. For exterior measurement, use the exterior square footage calculator.
Are the results ANSI Z765 compliant?
The math is the same methodology ANSI Z765 specifies. Whether the resulting figure qualifies as ANSI-compliant GLA depends on whether you input only above-grade, finished, heated and cooled space. The calculators don't enforce that classification.
Do I need an account to use the calculators?
No account, no signup, no email required for any calculator on this page. Just open the calculator and start using it.
Can I use these for a professional appraisal report?
The calculators support appraisal workflow (price-per-sqft analysis, GLA, paired sales, cost approach, income approach, effective age, and more). The actual appraisal report still requires field measurement, comparables analysis, and a licensed appraiser's certification.