Convert Square Mile to Square Perch
Convert square miles to square perches instantly. 1 square mile = 102400 square perch — use the live calculator, the exact formula, a conversion table and worked examples. Also check the Square Perch to Square Mile converter for the reverse conversion.
Units explained
Square Mile
A square mile is an imperial unit of area equal to exactly 2,589,988.110336 m². It is used for measuring large land areas in the United States and the United Kingdom.
Derived by squaring the statute mile (5,280 feet). The mile was standardized via the 1959 International Yard and Pound Agreement.
Square miles are used for US and UK regional geography (county areas, lake sizes, large parks), national statistics, and military range descriptions. 1 mi² = 640 acres = 2.589988 km².
Mile dates to Roman antiquity; modern exact value standardized in 1959.
Square Perch
A square perch is identical to a square rod, equal to approximately 25.293 m². 'Perch' is the older English regional name for the same unit.
Identical in value to square rod and square pole; differs only in regional naming preference. 'Perch' is more commonly used in British and Irish historical contexts.
Square perches survive in some historical British property records, particularly in Ireland where the unit had legal status until the metric transition.
Standardized via the 1959 International Yard and Pound Agreement.
Square Mile to Square Perch conversion formula
The relationship between square miles and square perches:
To convert square miles to square perches, multiply the value in square miles by 102400. To reverse, multiply square perches by 9.765625e-6.
How to use this converter
Type a value into the calculator. The result in square perches updates as you type. Tap a quick value, copy the result with one click, or use the swap arrow to jump straight to the Square Perch to Square Mile converter for the reverse direction.
Step-by-step: convert square miles to square perches
- Write down the value in square miles (mi²).
- Multiply that value by the factor 102400.
- The product is the equivalent value in square perches (perch²).
- To reverse, multiply the square perch value by 9.765625e-6.
Worked examples
Example 1 — Convert 1 mi² to perch²:
1 × 102400 = 102400 perch²
Example 2 — Convert 100 mi² to perch²:
100 × 102400 = 1.024e+7 perch²
Square Mile to Square Perch conversion table
Standard reference values for converting square miles to square perches:
| Square Mile [mi²] | Square Perch [perch²] |
|---|---|
| 0.01 | 1024 |
| 0.1 | 10240 |
| 1 | 102400 |
| 2 | 204800 |
| 3 | 307200 |
| 4 | 409600 |
| 5 | 512000 |
| 10 | 1024000 |
| 20 | 2048000 |
| 30 | 3072000 |
| 40 | 4096000 |
| 50 | 5120000 |
| 100 | 1.024e+7 |
| 500 | 5.12e+7 |
| 1000 | 1.024e+8 |
Frequently asked questions
How many square perches is 1 square mile?
How do I convert square miles to square perches?
How do I convert square perches back to square miles?
How many square perches is 100 square miles?
Popular area unit conversions
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Metric / SI (5 units)
Imperial / US Customary (14 units)
Sources & references
Conversion factor (1 mi² = 102400 perch²) verified against the following authoritative sources:
- BIPM — The International System of Units (SI Brochure 9th ed.)
Official BIPM publication defining the seven SI base units (including the meter) and the rules for their use. The global authority on units of measurement.
- NIST — Guide to the SI
US National Institute of Standards and Technology reference covering the SI base and derived units with definitions and usage rules for US technical practice.
- NIST Special Publication 811 — Guide for the Use of the International System of Units
Detailed NIST guide covering exact conversion factors between SI and US customary units along with formatting and rounding conventions.
- NIST — Refinement of values for the yard and pound (Federal Register 1959)
The treaty (signed by US
- International Hydrographic Organization — Resolution on the Nautical Mile
International authority that standardised the nautical mile at exactly 1852 m in 1929 — the value adopted worldwide for sea and air navigation.