Square Miles to Square Kilometers Converter
Convert square miles to square kilometers instantly with our free online tool. Essential for city comparisons, geography research, and reading US statistics.
Area ConverterThe quick answer for 1 Square Miles — type any value below for the exact result
Square Miles
Square Kilometers
sq mi to sq km Conversion Formula
To convert square miles to square kilometers, multiply the value by 2.59. A mile is 1.60934 kilometers, and squaring that ratio gives the area factor of 2.59.
Square Miles and Square Kilometers Explained
Square Miles (mi2)
A square mile (sq mi, mi²) is the area of a square one mile — 5,280 feet — on each side, equal to 640 acres or 2.59 square kilometers. It is the scale unit of American geography: city land areas run from 22.8 sq mi (Manhattan) to 302.6 sq mi (NYC land), counties span hundreds of sq mi, and Rhode Island's 1,033.8 sq mi of land makes it the smallest state.
Where it is used: Square miles are used by the US Census Bureau, national park statistics, city planning offices, and English-language almanacs for large land areas.
Origin: The statute mile was fixed by an English act of 1593 at 5,280 feet; squaring it later became the standard US large-area unit as federal surveys gridded the West.
Square Kilometers (km2)
A square kilometer (sq km, km²) is the metric unit for large areas: a square 1,000 meters on each side, containing 100 hectares or one million square meters. World geography speaks in it — Paris spans 105.4 sq km, Lake Balaton 592 sq km, and Malta 316 sq km — making it the common language for comparing territories internationally.
Where it is used: Square kilometers are standard for country and city statistics outside the US, in UN and EU databases, and in scientific literature on land cover and ecology.
Origin: The kilometer entered the French metric system in 1795 as 1,000 meters; its square became the default large-area unit as metrication spread through the 19th and 20th centuries.
Square Miles to Square Kilometers Conversion Table
| Square Miles (mi2) | Square Kilometers (km2) |
|---|---|
| 0.1 mi2 | 0.259 km2 |
| 0.25 mi2 | 0.6475 km2 |
| 0.5 mi2 | 1.295 km2 |
| 1 mi2 | 2.59 km2 |
| 1.5 mi2 | 3.885 km2 |
| 2 mi2 | 5.18 km2 |
| 2.5 mi2 | 6.475 km2 |
| 3 mi2 | 7.77 km2 |
| 5 mi2 | 12.95 km2 |
| 7.5 mi2 | 19.425 km2 |
| 10 mi2 | 25.9 km2 |
| 15 mi2 | 38.85 km2 |
| 20 mi2 | 51.8 km2 |
| 25 mi2 | 64.75 km2 |
| 50 mi2 | 129.5 km2 |
| 100 mi2 | 259 km2 |
| 250 mi2 | 647.5 km2 |
| 500 mi2 | 1295 km2 |
Square Kilometers to Square Miles Conversion Table
| Square Kilometers (km2) | Square Miles (mi2) |
|---|---|
| 1 km2 | 0.3861003861 mi2 |
| 2 km2 | 0.7722007722 mi2 |
| 5 km2 | 1.9305019305 mi2 |
| 10 km2 | 3.861003861 mi2 |
| 20 km2 | 7.722007722 mi2 |
| 25 km2 | 9.6525096525 mi2 |
| 50 km2 | 19.305019305 mi2 |
| 100 km2 | 38.61003861 mi2 |
| 200 km2 | 77.2200772201 mi2 |
| 250 km2 | 96.5250965251 mi2 |
| 500 km2 | 193.0501930502 mi2 |
| 1000 km2 | 386.1003861004 mi2 |
Square Miles to Square Kilometers in Everyday Objects
Common real-world examples that make Square Miles and Square Kilometers easy to picture at a glance.
| Square Miles (mi2) | Square Kilometers (km2) | |
|---|---|---|
| Manhattan land area | 22.8 mi2 | 59.052 km2 |
| Washington, DC land area | 61.4 mi2 | 159.026 km2 |
| Central Park | 1.31 mi2 | 3.3929 km2 |
| Gibraltar | 2.6 mi2 | 6.734 km2 |
| New York City land area | 302.6 mi2 | 783.734 km2 |
| The Isle of Man | 220.8494208494 mi2 | 572 km2 |
| Rhode Island land area | 1033.8 mi2 | 2677.542 km2 |
When You Need Square Miles to Square Kilometers Conversions
Comparing City Footprints
Chicago's 227.7 sq mi converts to 589.74 sq km for a European reader deciding whether it sprawls more than Frankfurt's 248 sq km city region.
Wildfire Incident Reporting
US incident commands size fires in square miles; a 5 sq mi burn is 12.95 sq km in the international newswires that aggregate global fire data.
National Park Statistics
Yellowstone's 3,471 sq mi becomes about 8,990 sq km, letting travel writers rank it against Lapland's and Patagonia's metric-sized reserves.
County and Municipality Sizing
A 320 sq mi Western county converts to 828.8 sq km for grant applications that request service-area figures in metric units.
Related Area Conversions
How to Use
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1
Enter the Area in sq mi
Type the square-mile figure from the US source — for example, 22.8 sq mi for Manhattan's land area
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2
See the Square Kilometers
The result appears instantly: 22.8 sq mi = 59.05 sq km, the number international readers expect
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3
Copy or Reverse
Copy the figure into your article or report, or click Swap to convert a sq km statistic back into sq mi
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4
Check the Table
Scan the table for anchors like 5 sq mi = 12.95 sq km and 100 sq mi = 259 sq km while writing
Why Use Be Converter?
Instant Conversion
Get square miles in square kilometers in real time as you type — ideal for fact-checking geography articles on the fly
Precision Guaranteed
Applies the exact 2.59 factor implied by the mile's 1.60934 km definition in this tool's data — no rounded textbook shortcuts
Handy Reference Table
Territory sizes at a glance — 1 sq mi = 2.59 sq km, 50 sq mi = 129.5 sq km, 500 sq mi = 1,295 sq km — matching US city stats to world tables
Swap with One Click
Toggle back to sq km to sq mi instantly when a European figure needs to land in an American report
Free & Unlimited
No registration required. Convert every city, county, park, and country figure you research — always free
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Frequently Asked Questions
How many square kilometers are in 1 square mile?
How do I convert 5 square miles to sq km?
What is 100 sq mi in square kilometers?
Is a square mile bigger than a square kilometer?
Why do US geography statistics use square miles?
How many sq km is Manhattan?
How many sq km is 50 square miles?
How do I convert sq mi to sq km precisely?
About Square Miles to Square Kilometers Converter
Our free online square miles to square kilometers converter translates US land statistics for the metric world. City footprints, county sizes, national parks, lakes, and wildfire perimeters are all reported in square miles by American agencies and in square kilometers everywhere else. Whether you are a journalist, student, or analyst, this tool applies the exact factor of 2.59 sq km per sq mi to every figure you enter.
Expert Tips for sq mi to sq km Conversion
The 2.59 factor is a squared length ratio: 1.60934 km per mile, squared, gives 2.59 — so lengths convert by 1.60934 while areas convert by 2.59.
Memorize city anchors: Manhattan 22.8 sq mi = 59.05 sq km, Chicago 227.7 sq mi = 589.74 sq km, and NYC land 302.6 sq mi = 783.73 sq km.
For national parks, convert before comparing: Yellowstone at 3,471 sq mi is about 8,990 sq km — clearly larger than any national park in continental Europe.
Mental shortcut: multiply sq mi by 2.6 — a 320 sq mi county gives 832 sq km against the exact 828.8, close enough for conversation.
Land vs total area matters in geography: US figures often exclude water (NYC land 302.6 sq mi) while metric sources include it; convert the same basis on both sides.