Length & Distance Converter

A length converter translates distances between unit systems without memorizing factors. This calculator length converter handles millimeters, centimeters, meters, kilometers, inches, feet, yards, miles, nautical miles, and astronomical units — every value normalizes through the meter (SI base unit) for consistent results.

Whether you need conversion length units for a blueprint, shipping label, or travel plan, enter a number, pick From and To, and read the converted dimension instantly. No upload; all math runs in your browser.

The metric system scales by tens. A handy cm km mm m chart or km m cm mm conversion chart looks like this:

• 1 m = 100 cm = 1,000 mm
• 1 km = 1,000 m
• 1 mm = 0.1 cm = 0.001 m

Convert from mm to cm: divide by 10 (250 mm = 25 cm). Millimeter to cm conversion is the same operation. For conversion of mm to m, divide by 1,000 — 1,500 mm = 1.5 m. To go the other way on long spans, mm to km divides by 1,000,000 (one million mm per km).

Imperial and metric meet at exact definitions: 1 foot = 0.3048 m and 1 inch = 25.4 mm. A conversion ft to m multiplies feet by 0.3048 — 6 ft = 1.8288 m. Reverse: meters × 3.28084 = feet.

Fine tolerances use millimeters. Feet to mm convert (feet to millimeters): multiply feet by 304.8. Six feet = 1,828.8 mm. An mm to feet converter divides mm by 304.8 — 914.4 mm = 3 ft. Machinists and furniture plans often bounce between mm and fractional inches; this tool covers both.

Within imperial units: feet to yards converter — divide feet by 3 (9 ft = 3 yd). One mile = 5,280 ft exactly. For metric road distances, convert feet to km or use a feet to km converter: multiply feet by 0.0003048. Example: 10,000 ft ≈ 3.048 km.

Runners and pilots switch between km and miles; hikers read meters on maps but think in feet for elevation. One converter with every unit avoids chained rounding errors from manual intermediate steps.

A length conversion chart, units of measurement chart conversion, or units of measurements conversion table lists anchor pairs so you can sanity-check results. Common anchors:

• 1 in = 25.4 mm = 2.54 cm
• 1 ft = 12 in = 30.48 cm = 304.8 mm
• 1 yd = 3 ft = 0.9144 m
• 1 mi = 1,609.344 m = 1.609344 km
• 1 km = 0.621371 mi
• 1 nmi = 1,852 m (nautical mile)

The reference table below this calculator duplicates that chart interactively — change any input and the full row updates, which beats a static poster when you need an odd value like 2.37 m in feet.

To convert dimensions on a parcel, room, or component, convert each edge separately — length, width, height — in the same unit system before calculating volume. A shelf listed as 120 cm × 30 cm × 45 cm becomes 47.24 in × 11.81 in × 17.72 in for a US retailer listing.

Engineering drawings may dimension in mm while the purchase order quotes inches. Run each critical measurement through the converter and keep four decimal places until the final rounding step to match manufacturing tolerance.

Centimeters to foot size searches usually mean shoe sizing: measure foot length in cm, then compare against brand charts (often in cm, EU, or US sizes). This tool converts cm to inches or feet for charts that list imperial lengths — 26 cm ≈ 10.24 in ≈ 0.853 ft.

Shoe size numbering (US 9, EU 42) is not a direct unit conversion — brands use different lasts. Use this converter for the underlying length, then match the brand's size table. Foot width is a separate measurement.

Millimeters: machining, PCB layout, rainfall in some countries. Centimeters: body height, furniture, retail clothing. Meters / km: athletics, driving, geography. Inches / feet: US construction, TV screens, aviation altitude (feet). Miles / nautical miles: road distance vs marine/aviation charts.

Pick the unit your audience expects, convert once here, and paste the result. For repeated work, the interactive chart replaces printing a wall poster — especially when you need mm, cm, m, km, ft, and mi in the same session.