Convert

Square mile to Square kilometre

Exact answer: 1 mi² = 2.589988110336 km² (exact defined factor)

Square mile and Square kilometre describe the same quantity from the Area family but come from different systems of units. The factor is defined exactly. Areas appear in land registers, property listings, construction drawings and technical datasheets.

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UnitCloud is a local measurement lab for everyday work, engineering, IT, energy, mobility and design. Every conversion shows result, formula, base unit, rounding and the common mistake.

What do you want to convert?

From1 mi²

Result2.589988 km²

Factor1 mi² = 2.589988110336 km²

Source basisBIPM SI Brochure · NIST Guide to SI Appendix B

Examples

011 mi² = 2.589988 km²

Example value from the reference table. Internal calculation uses stored factors; display output is rounded.

02Common mistake

Area scales quadratically. A length factor is not automatically an area factor.

03Base unit: m²

1 mi² = 2589988.11034 m². Then the value is converted through the base unit m² into Square kilometre.

Table

Square mile to Square kilometre
Square mile	Square kilometre
1	2.589988
2	5.179976
5	12.949941
10	25.899881
50	129.499406
100	258.998811

Formula

1 mi² = 2589988.11034 m². Then the value is converted through the base unit m² into Square kilometre.

Sources

BIPM SI BrochureSI base units, prefixes and official SI context.NIST Guide to SI Appendix BNIST conversion-factor method and non-SI factors.

Related conversions

Hectare to Square metreha → m²Area Square metre to Hectarem² → haArea Acre to Square metreacre → m²Area Square metre to Square centimetrem² → cm²Area

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Factor origin

Factors come from the stored source family and are not derived from rounded display values.

Rounding rule

UnitCloud keeps calculating with stored factors and rounds only the displayed output by selected precision.

When not to use

Do not use as the sole basis for official, medical, safety-critical or contractual decisions.

Citation

Citation note: UnitCloud, conversion with formula, sources reviewed: September 2026. Area. Source basis: BIPM SI Brochure · NIST Guide to SI Appendix B.

Common questions

What is the factor for Square mile to Square kilometre?

1 mi² = 2.589988110336 km²

Which formula does Square mile to Square kilometre use?

1 mi² = 2589988.110336 m². Then the value is converted through the base unit m² into Square kilometre.

What is the most common mistake?

Area scales quadratically. A length factor is not automatically an area factor.

When should I verify the result?

Do not use as the sole basis for official, medical, safety-critical or contractual decisions.