Length & Distance Converters — All 44 Conversions

By EnginStack Engineering Team | Verified by engineers, built on NIST metrology standards About →

Read the Length Conversion Guide

Metric vs imperial history, the 1959 treaty, the Mars Climate Orbiter, the Gimli Glider, and systematic pitfalls across 5 engineering disciplines. 30 linked converters, exact constants, failure cases.

Open the full guide →

Inches

Inches to Centimeters 1 in = 2.54 cm. The conversion behind every global supply chain tolerance sheet. TV screens, furniture, PCB design. × 2.54 Centimeters to Inches 1 cm ≈ 0.3937 in. Metric product dimensions read as imperial. Common in apparel and packaging. ÷ 2.54 Inches to Millimeters 1 in = 25.4 mm. The machinist's constant. Every CNC program and tolerance callout uses this. × 25.4 Millimeters to Inches 1 mm ≈ 0.03937 in. Bolt sizes, sheet metal gauges, bearing bores — metric parts in imperial shops. ÷ 25.4 Inches to Feet 12 in = 1 ft. Construction framing, lumber lengths, human height. The US standard since before the revolution. ÷ 12 Feet to Inches 1 ft = 12 in. Converting architectural dimensions to shop drawings. Every US tape measure. × 12 Inches to Yards 36 in = 1 yd. Fabric, carpet, and football fields. Mostly retail and textile applications. ÷ 36 Yards to Inches 1 yd = 36 in. Textile manufacturing, sewing patterns, material takeoffs. × 36

Feet

Feet to Meters 1 ft = 0.3048 m. The bridge between US construction and international engineering. BIM, structural steel, aviation. × 0.3048 Meters to Feet 1 m ≈ 3.28084 ft. International building code translation. Metric blueprints for US contractors. ÷ 0.3048 Feet to Centimeters 1 ft = 30.48 cm. Human height for medical records. Every doctor's office outside the US. × 30.48 Centimeters to Feet 1 cm ≈ 0.03281 ft. Converting metric body measurements to imperial. Fitness, health, apparel. ÷ 30.48 Feet to Millimeters 1 ft = 304.8 mm. Precision manufacturing from architectural drawings. Steel detailing and fabrication. × 304.8 Millimeters to Feet 1 mm ≈ 0.003281 ft. Metric shop drawings into imperial framing dimensions. ÷ 304.8 Feet to Yards 3 ft = 1 yd. Concrete pours, landscaping, sports field dimensions. Every US contractor knows this cold. ÷ 3 Yards to Feet 1 yd = 3 ft. Excavation volumes, turf orders, pipeline trenching. The cubic yard starts here. × 3 Feet to Miles 5,280 ft = 1 mi. Land surveying, property lines, civil engineering. The Roman mille passus lives on. ÷ 5,280 Miles to Feet 1 mi = 5,280 ft. A mile is 5,280 feet because 8 furlongs × 660 feet — blame the 16th century. × 5,280

Meters & Centimeters

Meters to Centimeters 1 m = 100 cm. The base SI length unit divided into hundredths. Every metric tape measure. × 100 Centimeters to Meters 100 cm = 1 m. Converting smaller measurements into the SI base unit for calculations. ÷ 100 Meters to Millimeters 1 m = 1,000 mm. Engineering drawings always dimension in mm — avoids decimal points entirely. × 1,000 Millimeters to Meters 1,000 mm = 1 m. Converting shop dimensions back to SI base for structural analysis. ÷ 1,000 Meters to Kilometers 1,000 m = 1 km. Road distances, athletics tracks, geography. The daily-use metric distance unit. ÷ 1,000 Kilometers to Meters 1 km = 1,000 m. Converting map distances into working units for survey and civil engineering. × 1,000 Centimeters to Millimeters 1 cm = 10 mm. The simplest metric conversion — move the decimal one place. Shop floor habit. × 10 Millimeters to Centimeters 10 mm = 1 cm. Moving from machining precision to everyday dimensions. ÷ 10 Centimeters to Yards 1 cm ≈ 0.01094 yd. Uncommon but occasionally needed for textile and carpet imports. ÷ 91.44 Yards to Centimeters 1 yd = 91.44 cm. Fabric by the yard for metric pattern makers. Home sewing, tailoring. × 91.44

Miles & Kilometers

Miles to Kilometers 1 mi = 1.609344 km. The most-typed distance conversion. Road signs, marathon splits, GPS. × 1.609344 Kilometers to Miles 1 km ≈ 0.6214 mi. 5K = 3.1 miles, 10K = 6.2 miles. Every runner's mental math. ÷ 1.609344 Meters to Miles 1 m ≈ 0.0006214 mi. Track events: 1,600 m ≈ 0.994 mi — the metric mile that's 9.3 m short. ÷ 1,609.344 Miles to Meters 1 mi = 1,609.344 m. Converting race distances for international competition standards. × 1,609.344 Meters to Yards 1 m ≈ 1.0936 yd. Swimming: short course (25 yd) vs long course (50 m). Pool conversions. ÷ 0.9144 Yards to Meters 1 yd = 0.9144 m. Swimming, track and field, golf — sports are full of yard-to-meter conversions. × 0.9144

Nautical & Maritime

Nautical Miles to Kilometers 1 NM = 1.852 km. One minute of latitude at the meridian. The standard for all marine and air navigation. × 1.852 Kilometers to Nautical Miles 1 km ≈ 0.54 NM. Converting overland distances to navigation charts. ÷ 1.852 Nautical Miles to Miles 1 NM ≈ 1.1508 mi. A nautical mile is 15% longer than a statute mile. Boaters and pilots know this. × 1.15078 Miles to Nautical Miles 1 mi ≈ 0.869 NM. Converting road distances to nautical charts for coastal navigation. × 0.868976

Astronomical

Astronomical Units to Kilometers 1 AU = 149,597,870.7 km. The mean Earth-Sun distance, fixed by IAU in 2012. Solar system scale. × 149,597,870.7 Kilometers to Astronomical Units 1 km = 6.685 × 10⁻⁹ AU. Interplanetary mission planning. Useful above about 10 million km. ÷ 149,597,870.7 AU to Miles 1 AU ≈ 92,955,807 mi. The Earth-Sun distance in miles. NASA public communications. × 92,955,807 Miles to AU 1 mi ≈ 1.076 × 10⁻⁸ AU. Micro-scale within the solar system. Rarely practical but occasionally needed. ÷ 92,955,807 Light-Years to Kilometers 1 ly ≈ 9.461 × 10¹² km. The distance light travels in one Julian year. Stellar and galactic scales. × 9.461e12 Kilometers to Light-Years 1 km ≈ 1.057 × 10⁻¹³ ly. For perspective: Voyager 1 is about 0.0026 light-years out. Took 47 years. ÷ 9.461e12