Feet and Inches Calculator

Category: Various Measurements/Units
- November 06, 2025
| |

Perform arithmetic operations with measurements in feet and inches. Add, subtract, multiply, and divide imperial measurements with automatic conversion between units and decimal equivalents.

Measurement Input

feet
inches
5.5 feet = 66 inches
feet
inches
3.667 feet = 44 inches

Conversion Options

Quick Presets

Advanced Options

Imperial Measurement System

The imperial system uses feet and inches for length measurements. Understanding how to perform calculations with these units is essential for construction, carpentry, and many everyday applications.

Basic Units
  • Inch ("): Basic unit of length, 1/12 of a foot
  • Foot ('): 12 inches, basic unit for larger measurements
  • Yard: 3 feet or 36 inches
  • Mile: 5,280 feet or 1,760 yards
Common Fractions
  • 1/2" = 0.5": Half inch
  • 1/4" = 0.25": Quarter inch
  • 1/8" = 0.125": Eighth inch
  • 1/16" = 0.0625": Sixteenth inch
  • 3/4" = 0.75": Three quarters inch
  • 5/8" = 0.625": Five eighths inch
Conversion Factors
  • Feet to Inches: Multiply by 12
  • Inches to Feet: Divide by 12
  • Feet to Meters: Multiply by 0.3048
  • Inches to Centimeters: Multiply by 2.54
  • Meters to Feet: Multiply by 3.28084
  • Centimeters to Inches: Divide by 2.54
Arithmetic Operations
  • Addition: Add feet to feet, inches to inches, carry over when inches ≥ 12
  • Subtraction: Subtract feet from feet, inches from inches, borrow when needed
  • Multiplication: Convert to single unit, multiply, then convert back
  • Division: Convert to single unit, divide, then convert back
Common Applications
  • Construction: Building dimensions, material calculations
  • Interior Design: Room measurements, furniture placement
  • Woodworking: Cutting lists, project planning
  • Home Improvement: Measuring spaces, material estimation
  • Real Estate: Property dimensions, square footage

Quick Reference

Common Building Materials
  • 2×4 lumber: 1.5" × 3.5" actual
  • 2×6 lumber: 1.5" × 5.5" actual
  • Plywood: 4' × 8' sheets
  • Drywall: 4' × 8', 4' × 12' sheets
  • Standard door: 6'8" × 2'8"
Measuring Tools
  • Tape measure: Most common tool
  • Ruler: 12" standard length
  • Yardstick: 36" length
  • Folding rule: 6' typical length
  • Laser measure: Digital accuracy

Disclaimer: This calculator provides accurate conversions and calculations for feet and inches measurements. For critical applications, always verify measurements with appropriate tools and double-check calculations. Building codes and material specifications may have specific measurement requirements.

What Is the Feet and Inches Calculator?

The Feet and Inches Calculator is an easy-to-use tool designed to perform accurate arithmetic operations with imperial units—specifically feet and inches. Whether you're adding, subtracting, multiplying, or dividing measurements, this calculator simplifies the process by automatically converting between units and displaying results in multiple formats, including metric.

It's especially useful for those working in construction, carpentry, home improvement, or interior design—fields where precise measurement is essential. This measurement converter acts as both a calculator and a unit conversion tool, helping users handle imperial measurements with confidence and speed.

Formula Used in the Calculator

Feet and Inches to Inches:
Total Inches = (Feet × 12) + Inches

Inches to Feet and Inches:
Feet = Floor(Total Inches ÷ 12)
Inches = Total Inches mod 12

Feet to Meters:
Meters = Feet × 0.3048

Inches to Centimeters:
Centimeters = Inches × 2.54

How to Use the Calculator

Follow these steps to use the calculator effectively:

  • Enter Two Measurements: Input values for feet and inches for each of the two measurements.
  • Select an Operation: Choose to add, subtract, multiply, or divide the two measurements.
  • Choose Input and Output Formats: Convert measurements to or from decimal feet, total inches, or metric (meters, centimeters).
  • Adjust Settings: Set decimal precision, select how fractions are displayed, and toggle extra info like formulas and conversions.
  • Click "Calculate": View detailed results including conversion values, calculation steps, and practical usage suggestions.

Why Use This Calculator?

This tool goes beyond simple arithmetic. Here's how it can help:

  • Quick Unit Conversions: Instantly convert between feet, inches, metric units, and decimal values.
  • Smart Fraction Handling: View measurements in decimal, fractional, or mixed formats.
  • Visual Learning: See step-by-step calculations and applied formulas for better understanding.
  • Practical Applications: Receive suggestions for real-world uses of your result, from construction to interior design.
  • Preset Buttons: Load common measurements like standard doors or lumber sizes for faster input.

Who Is It For?

This calculator is valuable for both professionals and DIY users. Whether you're cutting materials, planning room layouts, or estimating project sizes, this conversion helper ensures precision without manual conversions. It also doubles as a Conversion Calculator for educational and occupational use, making it a useful reference tool.

Frequently Asked Questions (FAQ)

  • Can I convert metric values? Yes. The tool supports input and output in meters and centimeters, making it a unit conversion tool as well.
  • Does it support fractional inches? Absolutely. You can switch to fraction or mixed formats to view results like "6 1/2”" instead of "6.5”.
  • What if I only know total inches? Use the "Total Inches" input format to enter your values directly.
  • Can I see how the result was calculated? Yes. Enable the “Show calculation steps” checkbox to view detailed steps.
  • Is this suitable for metric conversions? Yes. It acts as a measurement converter between imperial and metric units.

Examples of Practical Use

Here are some real-world scenarios where this tool can save time and reduce errors:

  • Planning lumber cuts for a woodworking project
  • Estimating material needed for drywall or flooring
  • Calculating room dimensions for furniture placement
  • Converting old construction plans into metric
  • Checking if appliances will fit in designated spaces

Final Thoughts

The Feet and Inches Calculator simplifies the process of working with imperial measurements, offering both arithmetic capabilities and seamless unit conversion. Whether you're dealing with feet, inches, or metric units, this tool acts as a reliable value conversion and measurement calculator—perfect for both personal and professional tasks.