Length & Distance Converter

Length measures distance between two points. This 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.

Enter a number, pick From and To, and read the converted dimension instantly. Use it for blueprints, shipping labels, travel planning, or homework. All math runs in your browser; nothing is uploaded.

The metric system scales by tens. A handy reference chart looks like this:

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

To convert millimeters to centimeters, divide by 10 (250 mm = 25 cm). To convert millimeters to meters, divide by 1,000 — 1,500 mm = 1.5 m. For long spans, millimeters to kilometers divides by 1,000,000.

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

Fine tolerances use millimeters. Feet to millimeters: multiply feet by 304.8. Six feet = 1,828.8 mm. Millimeters to feet: divide 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, divide feet by 3 for yards (9 ft = 3 yd). One mile = 5,280 ft exactly. For metric road distances, multiply feet by 0.0003048 for kilometers. 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 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.

For shoe sizing, measure foot length in cm, then compare against brand charts. 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.