Miles to Kilometers Converter
Instantly convert miles to kilometers, meters, yards, and more — with live precision control, quick presets, and a downloadable PDF report.
Uses the exact factor 1 mile = 1.609344 km (international defined constant) — for reference only.
| Miles | Kilometers | Meters | Yards |
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Miles to Kilometers Conversion — Complete Guide for 2026
Converting miles to kilometers is one of the most frequent distance-unit conversions in everyday life — arising whenever a U.S. or U.K. road distance, athletic race result, or GPS reading needs to be expressed in the metric system used by the rest of the world. The entire conversion rests on one exact, internationally defined relationship: 1 mile = 1.609344 kilometers exactly.
Our free Miles to Kilometers Converter performs this calculation with up to 8 decimal places and automatically outputs results across the full unit ladder — kilometers, meters, yards, feet, centimeters, millimeters, nautical miles, and inches — alongside a live logarithmic bar chart and a downloadable 2-page PDF report formatted for professional documentation.
How to Use the Miles to Kilometers Converter in 4 Steps
A complete conversion takes under five seconds. Enter your mile value, set your precision, review every unit output simultaneously, and download a PDF report for race documentation, logistics records, or project archives.
Enter Your Mile Value
Type any distance in miles — whole numbers or decimals both work. The calculator handles everything from short distances (0.25 mi) to transcontinental journey distances, all with identical mathematical accuracy. Use the Quick Preset chips for the most common distances: 1 mi, 5 mi, 10 mi, Marathon (26.2188 mi), 100 mi, 500 mi. Results update live on every keystroke — no Convert button click required.
Set Decimal Precision
Choose between 0 and 8 decimal places using the input field or the precision slider. Use 0–2 for road signage, general travel, and everyday estimates; 3–4 for athletic records, race course certification, and logistics documentation; and 6–8 for maritime navigation, geodetics, and scientific research. The slider and number input stay in sync — adjust either and all results recalculate instantly.
Review the Full Breakdown
The hero result shows your primary kilometers value in large type with a sub-line confirming meters and yards. Three summary cards display kilometers, meters, and yards at a glance. The full conversion grid adds feet, centimeters, millimeters, nautical miles, and inches — all derived from the same exact calculation. The logarithmic bar chart maps five primary unit magnitudes visually, making the enormous span between millimeters and kilometers immediately comprehensible.
Download Your PDF Report
Click Download PDF for a professionally formatted 2-page report. Page 1 includes the branded header, hero result card, imperial/metric side-by-side breakdown table, six labeled summary cards, and chart snapshot. Page 2 adds a 15-row reference table (0.25 mi to 1000 mi) with athletic anchors labeled and the row nearest your input highlighted in blue — formatted for race records, logistics packages, and project archives.
Why 1 Mile = 1.609344 Kilometers Exactly
The mile has ancient origins — derived from the Roman mille passuum (one thousand double-paces, approximately 1480 meters) — that evolved through medieval English usage into the statute mile of exactly 5280 feet. The kilometer, by contrast, was defined by French scientists in 1793 as one ten-thousandth of the meridional distance from the North Pole to the equator. These two units originated in entirely separate historical traditions, which is why their ratio is not a round number.
The precise metric equivalent of the mile was fixed on July 1, 1959, when six English-speaking nations signed the International Yard and Pound Agreement. Under that treaty, the yard was defined as exactly 0.9144 meters. Since 1 mile = 1760 yards, it follows that: 1 mile = 1760 × 0.9144 = 1609.344 meters = 1.609344 km exactly. Every decimal place in this number is a mathematical consequence of the defined chain — not a measurement, not a rounded estimate.
Why miles to km produces clean terminating decimals
Unlike the km-to-miles direction (where dividing by 1.609344 yields a non-terminating repeating decimal), multiplying miles by 1.609344 always produces a terminating decimal. That is because 1.609344 itself is a terminating decimal — and multiplying any number by a terminating decimal always produces a terminating decimal result. This means 1 mile = exactly 1.609344 km, 10 miles = exactly 16.09344 km, and the marathon (26.21875887… miles) = exactly 42.195 km. The “clean” direction of the conversion is miles to km, not km to miles.
For most practical purposes — road signs, athletic results, logistics planning — 3–4 decimal places provide more than sufficient accuracy. For formal athletic certification and geodetic surveying, 6–8 places covers all precision requirements, since the double-precision floating-point arithmetic used here is accurate to approximately 15 significant digits.
What the Miles to Kilometers Converter Calculates
Every output is derived from the same single multiplication — no intermediate rounding between units — giving you a complete imperial and metric breakdown from one instant calculation.
Decimal Kilometers (Hero Result)
The primary conversion multiplies your mile value by the exact constant 1.609344 to produce decimal kilometers. This is the format used on European road signs, in international athletics documentation, GPS navigation in metric mode, and logistics shipping records in the vast majority of countries. Because 1.609344 is a terminating decimal, every whole-number or simple-fraction mile value converts to a finite, exact decimal in kilometers — making this the “clean” direction of the conversion.
Meters (Cross-Reference)
Meters (miles × 1609.344) provide the baseline metric distance without unit scaling — essential for race course verification, since World Athletics certifies all competition distances in meters. A 5-mile race is 8046.72 meters; confirming this value is standard practice when submitting road race courses for official certification. Meters also serve as a sanity check: if your km output looks plausible but the meters figure looks wrong for the context, a data-entry error is likely.
Yards & Feet
Yards (miles × 1760) are an exact conversion — the mile is defined as 1760 yards — giving whole-number yard results for every whole-number mile input. The traditional marathon is described as 26 miles 385 yards, and the yards output lets you express any mile-based distance in this mixed format. Feet (miles × 5280, also exact) appear in U.S. aviation altitude references, construction elevation specs, and depth measurements across infrastructure projects.
Nautical Miles
Nautical miles (miles × 1609.344 ÷ 1852) convert your statute mile value into the unit used by international maritime navigation and commercial aviation. One nautical mile equals exactly 1852 meters — defined as one arc-minute of latitude on Earth’s surface. Knowing both statute-mile and nautical-mile equivalents of a U.S. land distance is essential when planning coastal voyages, comparing ATC radar range data, or reconciling road-distance freight quotes with sea-leg shipping manifests. Output uses 6 decimal places for navigation-grade precision.
Visual Bar Chart
A horizontal five-bar chart plots the numeric magnitude of your value across miles, kilometers, meters, yards, and feet in five distinct colors on a logarithmic scale. The log scale is essential — for 1 mile, meters (1609.344) is three orders of magnitude larger than miles (1.0). Without log scaling, the miles bar would be invisible next to the meters bar. The log axis keeps all five bars visible and meaningfully proportioned, with M/k suffixes on axis labels to prevent crowding at large values.
2-Page PDF Report
Page 1 contains the branded header, hero result, imperial/metric breakdown table, six summary cards (input mi, km, meters, yards, feet, nautical miles), and chart snapshot. Page 2 contains a 15-row reference table spanning 0.25 mi to 1000 mi with athletic anchors labeled (1 mi, 5K equivalent, marathon, 100 mi ultramarathon) and the row nearest your input highlighted in blue. Formatted for race documentation, logistics shipping records, navigation voyage logs, and project audit files.
Miles to Kilometers Conversion Chart — Common Values
Every value in this table is computed using the exact constant 1.609344. Athletic distances (highlighted) are internationally standardized by World Athletics and shown with their full mile and kilometer equivalents.
| Miles | Kilometers | Meters | Yards | Common Reference |
|---|---|---|---|---|
| 0.25 mi | 0.4023 km | 402.3 m | 440 yd | Quarter mile — standard drag strip distance |
| 0.5 mi | 0.8047 km | 804.7 m | 880 yd | Half mile — common training interval |
| 1 mi | 1.6093 km | 1,609.3 m | 1,760 yd | 1 statute mile — exact defined constant |
| 1.5 mi | 2.4140 km | 2,414.0 m | 2,640 yd | Common warm-up / cool-down run |
| 2 mi | 3.2187 km | 3,218.7 m | 3,520 yd | Standard U.S. Army fitness test distance |
| 3 mi | 4.8280 km | 4,828.0 m | 5,280 yd | Common beginner race distance |
| 3.107 mi | 5.0000 km | 5,000.0 m | 5,467 yd | 5K road race — Parkrun distance |
| 5 mi | 8.0467 km | 8,046.7 m | 8,800 yd | 5-mile road race — popular U.S./U.K. event |
| 6.214 mi | 10.000 km | 10,000.0 m | 10,936 yd | 10K race — Olympic track distance |
| 10 mi | 16.093 km | 16,093.4 m | 17,600 yd | 10-mile road race — common U.S./U.K. event |
| 13.109 mi | 21.097 km | 21,097.0 m | 23,072 yd | Half marathon — World Athletics standard |
| 26.219 mi | 42.195 km | 42,195.0 m | 46,145 yd | Marathon — 26 miles 385 yards |
| 50 mi | 80.467 km | 80,467.2 m | 88,000 yd | 50-mile ultramarathon distance |
| 0.621 mi | 1.0000 km | 1,000.0 m | 1,094 yd | Exactly 1 kilometer — metric reference anchor |
| 100 mi | 160.934 km | 160,934.4 m | 176,000 yd | 100-mile ultramarathon — Western States standard |
| 1000 mi | 1609.344 km | 1,609,344.0 m | 1,760,000 yd | Exactly 1000 miles — long-haul journey reference |
Highlighted rows mark exact kilometer values or internationally standardized athletic distances.
Converting Race Distances: Miles to Kilometers
Athletics is one of the most common contexts for miles-to-km conversion. American and British road events are frequently described in miles, while World Athletics standardizes all competition distances in meters and kilometers. The tables below cover the full range of standard track, road, and ultra-distance events in both miles and km — useful for athlete profiles, press releases, GPS watch configuration, and international media coverage.
| Track / Field Event | Miles | Kilometers |
|---|---|---|
| 400 m sprint | 0.249 mi | 0.400 km |
| 800 m middle distance | 0.497 mi | 0.800 km |
| 1500 m race | 0.932 mi | 1.500 km |
| 1 mile race | 1.000 mi | 1.609 km |
| 3000 m steeplechase | 1.864 mi | 3.000 km |
| 5000 m track race | 3.107 mi | 5.000 km |
| 10000 m track race | 6.214 mi | 10.000 km |
| 20 km race walk | 12.427 mi | 20.000 km |
| Road / Ultra Event | Miles | Kilometers |
|---|---|---|
| 5K road race (Parkrun) | 3.107 mi | 5.000 km |
| 5-mile road race | 5.000 mi | 8.047 km |
| 10K road race | 6.214 mi | 10.000 km |
| 10-mile road race | 10.000 mi | 16.093 km |
| Half marathon | 13.109 mi | 21.097 km |
| Marathon | 26.219 mi | 42.195 km |
| 50-mile ultramarathon | 50.000 mi | 80.467 km |
| 100-mile ultramarathon | 100.000 mi | 160.934 km |
Miles to Kilometers — Key Conversion Numbers
The Miles to Kilometers Converter Is Built For You If…
Whether you’re a runner converting an American race result into metric for an international leaderboard, a traveler making sense of U.S. road signs from a metric country, or a logistics professional reconciling imperial freight quotes with metric documentation — this converter delivers an exact, downloadable result in seconds.
Runners, Cyclists & Athletes
Race distances, training plans & international recordsU.S. and U.K. road events are measured in miles, but World Athletics records all competition distances in meters and kilometers. A runner completing a 10-mile personal record needs the exact km equivalent to submit to an international race database or European running club leaderboard. A cyclist logging rides on a platform used internationally needs both units displayed simultaneously for meaningful cross-border comparison.
- Use 3–4 decimal precision for official athletic records and race results
- Use the Marathon preset chip to instantly get 26.2188 mi = 42.195 km
- Use the yards output to verify the traditional “26 miles 385 yards” marathon format
- Export PDF for meet programs, press release fact sheets, and race documentation archives
International Travelers & Drivers
Road signs, GPS navigation & journey planningVisitors from metric countries driving in the United States or United Kingdom encounter speed limits and road distances in miles. The critical need arises immediately: “this sign says 65 mph — how fast is that in km/h?” or “the next exit is 12 miles — how far is that really?” Conversely, Americans reviewing an international itinerary need to quickly cross-check their familiar mile-based mental map against metric route plans from European travel agencies or mapping apps.
- Use 1–2 decimal precision for road distance estimates — more than enough for navigation
- Bookmark: 1 mile ≈ 1.609 km, 60 mph = 96.56 km/h, 100 mph = 160.93 km/h
- Use the 10 mi and 100 mi presets for typical highway navigation distances
- Cross-check the meters output for shorter distances — walking distances, parking distances
Logistics, Maritime & Aviation Professionals
Shipping routes, navigation & freight documentationInternational logistics professionals routinely bridge mile-based U.S. freight distances with the metric shipping manifests required for European, Asian, and Latin American customs documentation. Container ship voyage plans express distances in nautical miles; road freight legs in the U.S. appear in statute miles; destination distances in Europe appear in km. Reconciling all three in a single, verifiable calculation — and producing a PDF record for the shipping file — is precisely what this converter is built to do.
- Use the nautical miles output for maritime and aviation route planning — 1 NM = 1852 m exactly
- Use 6+ decimal precision for navigation calculations and geodetic distance verification
- Use the 500 mi preset for long-haul route estimates and compare directly with km-based mileage charts
- Export PDF to attach to voyage records, shipping manifests, and customs compliance files
7 Tips for Accurate Miles to Kilometers Conversions
Multiplying by 1.609344 is straightforward, but a few professional habits prevent the errors that surface when imperial distances meet metric documentation, athletic records, or international navigation systems.
Always Use 1.609344 — Not 1.6
Using 1.6 instead of 1.609344 introduces a 0.58% error — about 580 meters per 100 miles. On a marathon of 26.219 miles, that is 152 meters of error — more than half a lap of a standard track. For driving, 100 miles reads as 160.00 km instead of 160.934 km — nearly a kilometer of difference. The exact constant is 1.609344. Round the result to your chosen precision, never the conversion factor itself.
Memorize Six Essential Mile-to-KM Anchors
For everyday use, six anchors cover almost everything: 1 mi = 1.609 km, 5 mi = 8.047 km, 10 mi = 16.093 km, 13.109 mi = 21.097 km (half marathon), 26.219 mi = 42.195 km (marathon), and 100 mi = 160.934 km. Knowing these lets you instantly sanity-check any result — if a 10-mile run comes back as 1.609 km, you know the decimal point is in the wrong place. If a marathon shows as 4.2195 km, the input was in km not miles.
Understand Why Miles × 1.609344 Always Terminates
Because 1.609344 is itself a terminating decimal, multiplying any mile value by it always produces a terminating decimal result in kilometers — unlike the reverse direction (km ÷ 1.609344), which produces non-terminating repeating decimals. This means 1 mile = exactly 1.609344 km, 10 miles = exactly 16.09344 km, and a marathon of 26 miles 385 yards = exactly 42.195 km. Miles to km is the “clean” direction of the conversion; display rounding is a presentational choice, not a mathematical necessity.
Know the Difference Between Statute Miles and Nautical Miles
A statute mile (the standard road mile) = 1.609344 km. A nautical mile = 1.852 km exactly — about 15% longer. The two units are completely different despite sharing the word “mile.” Confusing them in maritime or aviation contexts produces serious navigation errors: 100 statute miles is 160.93 km, while 100 nautical miles is 185.2 km — a 24 km difference. The calculator outputs nautical miles separately under “NM” specifically to prevent this error.
Match Decimal Precision to the Application
0–1 decimal places for road signs, general travel, and casual conversation; 2–3 for race announcements, training plans, and logistics planning; 4–5 for official athletic records and course certification; 6–8 for navigation, geodetics, and scientific calculations. Higher precision than needed is harmless. Too low can introduce rounding differences that accumulate over multi-leg routes, affect distance-dependent fuel calculations, or fail official timing system distance verifications.
Use the Yards Output to Express Traditional Race Distances
Some athletic distances are defined in yards and miles, and communicating them in the traditional mixed format requires the yards output. A marathon is officially 26 miles 385 yards — not 26.219 miles. Expressing a half marathon as 13 miles 192 yards (rather than 13.109 miles) may be required in certain officiating contexts, U.K. athletics documentation, or historical comparison tables. The yards output (miles × 1760, an exact integer relationship) gives you this value directly, with no secondary calculation required.
Use the PDF as a Permanent Distance Record
For professional deliverables — race course documentation, shipping manifest distance records, logistics route calculations, navigation voyage logs, or international construction site-plan dimensions — download the PDF conversion report and attach it to your project file. It records the exact input in miles, all converted outputs at your chosen precision, the conversion standard, and the generation date. For any distance where accuracy is later questioned, the PDF provides a timestamped, auditable record of the conversion.
Miles to Kilometers Converter — Frequently Asked Questions
Everything you need to know about converting miles to kilometers, the history of the 1.609344-km mile definition, athletic distance standards, nautical miles, and how to apply this calculator accurately across travel, sport, logistics, and everyday projects.
To convert miles to kilometers, multiply the mile value by 1.609344. The formula is: km = miles × 1.609344. For example, 10 miles × 1.609344 = 16.09344 kilometers.
The factor 1.609344 is the exact international defined constant — derived from 1 yard = 0.9144 m (International Yard and Pound Agreement, 1959), giving 1 mile = 1760 yards = 1609.344 m = 1.609344 km exactly. Because 1.609344 is a terminating decimal, every mile value converts to a terminating (exact, finite) decimal in kilometers. The calculator uses this exact constant for all calculations; only the displayed result is rounded to your chosen precision.
1 mile equals exactly 1.609344 kilometers — an exact defined constant, not a rounded measurement. This value is precise to infinite decimal places, established by the International Yard and Pound Agreement of 1959.
Key anchors: 1 mi = 1.609 km · 5 mi = 8.047 km · 10 mi = 16.093 km · 26.219 mi = 42.195 km (marathon). A quick mental estimate: 1 mile is roughly 1.6 km. The fastest mental shortcut: multiply miles by 8 and divide by 5 (same as × 8/5 = × 1.6), which gives a result within 0.58% of the true value.
The exact formula is: km = miles × 1.609344. The constant 1.609344 is an exact defined value — not a measurement, not an approximation. To reverse: miles = km ÷ 1.609344.
Quick anchors: 1 mi = 1.609 km · 5 mi = 8.047 km · 10 mi = 16.093 km · 100 mi = 160.934 km. Because 1.609344 is a terminating decimal, every mile value converts to a terminating decimal in km. This makes miles-to-km the “clean” direction of the conversion — the displayed result is rounded only as a presentational preference, not because the math requires it.
The exact metric equivalent of the mile was fixed by the International Yard and Pound Agreement of 1959, signed by the United States, United Kingdom, Canada, Australia, New Zealand, and South Africa. Under that treaty, 1 yard was defined as exactly 0.9144 meters. Since 1 mile = 1760 yards: 1 mile = 1760 × 0.9144 = 1609.344 meters = 1.609344 km exactly.
The complete chain of exact definitions: 1 inch = 25.4 mm exactly; 1 foot = 12 inches = 304.8 mm; 1 yard = 3 feet = 914.4 mm = 0.9144 m; 1 mile = 1760 yards = 1609.344 m. Every link in this chain is mathematically exact, making 1.609344 an exact constant — not a rounded figure — valid to infinite decimal places. The 1959 Agreement was recognized by the U.S. NIST and the International Bureau of Weights and Measures (BIPM) and remains the authoritative standard today.
A marathon is 26 miles and 385 yards, which equals exactly 42.195 kilometers (42,195 meters). The precise calculation: 26 miles 385 yards = 26.21875887… miles × 1.609344 = 42.195 km — a terminating decimal because 1.609344 terminates and the official yard-based distance definition is an exact integer relationship.
The 42.195 km standard was adopted by the IAAF (now World Athletics) in 1921. It traces to the 1908 London Olympics, where the course was set at 26 miles 385 yards to start at Windsor Castle and finish in front of the Royal Box. The exact km value (42.195) is used in GPS watch course verification, official certification submissions, and international race result databases. Use the Marathon preset chip in the calculator for the instant full breakdown.
10 miles equals exactly 16.09344 kilometers, or 16,093.44 meters. The calculation: 10 × 1.609344 = 16.09344 km exactly — a perfectly terminating decimal.
10 miles is a popular road race distance in the United States and United Kingdom — the Great South Run (Portsmouth) and Great Manchester Run both feature 10-mile formats. It is also a benchmark training distance for intermediate runners progressing beyond the 10K. In driving terms, 10 miles at 60 mph is exactly 10 minutes. The 16.09 km equivalent is useful when logging U.S. training runs into European platforms or comparing 10-mile race times against the 15K road race (15.000 km) in international results databases. Use the 10 mi preset chip for the instant full breakdown.
5 miles equals exactly 8.04672 kilometers, or 8,046.72 meters. The calculation: 5 × 1.609344 = 8.04672 km exactly.
5 miles is a popular road race distance in the U.S. and U.K. — the Bupa Great Edinburgh Run and thousands of local charity events use this format. It is also a common training milestone for runners bridging the gap between 5K and 10K. Note that 5 miles (8.047 km) is slightly longer than the international 8K road race distance (8.000 km) — a difference of 47 meters. Use the 5 mi preset chip in the calculator for the instant full breakdown across all units.
100 miles equals exactly 160.9344 kilometers, or 160,934.4 meters. The calculation: 100 × 1.609344 = 160.9344 km exactly.
100 miles is a defining benchmark in ultramarathon running — the Western States Endurance Run, the Leadville 100, and the Centurion Running Grand Slam all use 100-mile formats. The 160.93 km equivalent is used when comparing these events with European ultras (which typically use km designations), for international press coverage, and for GPS course verification. In driving terms, 100 miles at 60 mph is 1 hour 40 minutes; the 160.93 km figure helps European drivers understand the scale. Use the 100 mi preset chip for the full breakdown.
The statute mile is an imperial unit used primarily in the United States and for road distances in the United Kingdom — equal to 5280 feet = 1760 yards = 1609.344 meters. The kilometer is the SI (International System of Units) unit used globally — equal to 1000 meters. A mile is larger than a kilometer: the same road distance reads as a smaller number in miles than in km.
Practical differences: speed limits look dramatically different across the Atlantic — 60 mph = 96.56 km/h, so a 60 mph U.S. highway is comparable to a 100 km/h European motorway. Highway distances also look very different: a 300-mile road trip sounds modest in the U.S. but is 482.8 km, which sounds like a significant journey in European terms. Neither unit is more accurate; the conversion is exact and mathematically clean in both directions.
The United States is the most prominent country using miles for road distances, speed limits, and everyday navigation. The United Kingdom uses miles for road signs and speed limits, though km is standard in scientific, mapping, and athletics contexts. Liberia and Myanmar officially use miles, though km is widely used in practice in both.
All other countries — including all of continental Europe, Canada, Australia, New Zealand, all of Asia, Latin America, and Africa — use kilometers as the primary road distance unit. International commercial aviation uses nautical miles (1 NM = 1.852 km), not statute miles. World Athletics standardizes all competition distances in meters and kilometers regardless of host country.
The calculator uses the exact relationship 1 mile = 1.609344 km with double-precision floating-point arithmetic, accurate to approximately 15 significant digits. The display rounds only to your chosen decimal precision — the underlying calculation always uses the full exact constant.
Because 1.609344 is a terminating decimal, multiplying any mile value by it produces a mathematically exact result in km — every displayed digit is correct to within floating-point precision limits (approximately 15 significant figures), with no inherent repeating-decimal truncation. For athletic records and race course certification, 4–6 decimal places provide sub-meter accuracy. For navigation and geodetic applications, 8 decimal places covers all precision requirements. The downloadable PDF records all output values, your chosen precision, and the conversion standard, creating a complete auditable record for professional documentation.
Accuracy note: The HomeExpertly Miles to Kilometers Converter uses the exact international conversion relationship of 1 mile = 1.609344 kilometers, derived from 1 yard = 0.9144 meters as established by the 1959 International Yard and Pound Agreement and recognized by the U.S. National Institute of Standards and Technology (NIST) and the International Bureau of Weights and Measures (BIPM). Because 1.609344 is a terminating decimal, every mile input converts to a mathematically exact terminating decimal in kilometers; displayed results are rounded only to your chosen presentation precision. All calculations are mathematically precise to the decimal precision you select (up to 8 places). Results are for informational and reference purposes only. For applications where distance accuracy is critical — including but not limited to official race course certification, maritime navigation, aviation route planning, geodetic surveying, legally binding transport contracts, customs and shipping documentation, or scientific publication — always verify your conversions independently and use calibrated measurement instruments or authoritative navigation systems. The nautical mile output uses the international definition of 1 NM = 1852 meters exactly; statute miles and nautical miles are not interchangeable and must not be confused in navigation contexts. HomeExpertly is not responsible for any consequences arising from the use of these conversions, including navigation errors, missed destinations, failed athletic certifications, freight mismeasurements, or project rework. When in doubt, use the highest available precision, cross-check against a secondary source, and consult a licensed professional for measurement-critical applications.