Convert Square Inch to Rai (in² → rai)
The square inch measures American printer paper coverage, manufacturing tolerances, and small surface areas.
Square Inch to Rai Conversion Table
10 common values| Square Inch | Rai |
|---|---|
| 1 in² | 4.032e-7 rai |
| 5 in² | 0.000002016 rai |
| 10 in² | 0.000004032 rai |
| 50 in² | 0.00002016 rai |
| 100 in² | 0.00004032 rai |
| 500 in² | 0.000202 rai |
| 1,000 in² | 0.000403 rai |
| 5,000 in² | 0.002016 rai |
| 10,000 in² | 0.004032 rai |
| 50,000 in² | 0.020161 rai |
How to Convert Square Inch to Rai Manually
Step by StepConverting square inches to rais is straightforward: multiply by the conversion factor. Follow these three steps to do it by hand or in your head.
- 1Take your value in square inchesStart with the number of square inches (in²) you want to convert.
- 2Multiply by 4.032e-7The conversion factor from in² to rai is 4.032e-7. Multiply your value by this number.
- 3Read the result in raisThe result is your value in rais (rai).
Formula
Multiply the value in square inches by 4.032e-7. For the reverse direction, multiply by 2,480,005.
rai = in² × 4.032e-7in² = rai × 2,480,005Tips
Use these in everyday conversions- 1 in² = 6.4516 cm² = 0.0069 ft².
- 144 in² = 1 ft² exactly.
- PSI means pounds per square inch — relevant for tyre pressure, hydraulics.
Common Mistakes
Avoid these- Mixing in² with in or in³ — different dimensions.
- Using 6.5 cm² shortcut — correct 6.4516 cm² differs by 0.7%.
- Assuming US and UK square inches differ — they do not.
About Square Inch and Rai
What is the Square Inch?
The square inch equals exactly 6.4516 square centimeters and is the American precision unit for printer paper coverage, manufacturing tolerances, and small-area calculations. Pressure in the US is measured in pounds per square inch (psi), so the unit is essential in engineering and tire-pressure ratings. Computer screens are sometimes specified by total viewable square inches. The square inch relates to the square foot (144 in² = 1 ft²), the square centimeter (1 in² = 6.4516 cm²), the square millimeter (1 in² ≈ 645.16 mm²), and the square meter (1 in² ≈ 0.000645 m²). Postage-stamp areas, electronic-circuit board details, and machined-part tolerances all use square inches in American engineering practice.
- US machine engineering and drawings
- Tile, flooring and surface specifications
- Pressure units (PSI) base area
A US letter page is 93.5 in². A common US tile is 144 in² (1 ft²). Credit card ≈ 7.1 in².
What is the Rai?
The rai equals exactly 1,600 square meters (40 m × 40 m) and is the traditional Thai land unit, still officially used in Thailand for real estate, agriculture, and property records. The rai is divided into 4 ngan (each 400 m²), and 1 ngan equals 100 wa (each 4 m²). Despite Thailand's adoption of the metric system, the rai remains the everyday unit for buying and selling land in Thai contexts — a small urban plot might be 1 rai, while rural farms are quoted in tens or hundreds of rai. The rai relates to the square meter (1 rai = 1,600 m²), the hectare (1 ha = 6.25 rai), and the acre (1 acre ≈ 2.529 rai). The rai's exact metric definition (1,600 m²) makes conversion to SI units precise, unlike many traditional land units.
- Thai rural property and farmland
- Thai real-estate listings
- Agricultural yield reporting in Thailand
A small Thai farm might be 10–20 rai (1.6–3.2 ha). Thai rice yields: 400–600 kg per rai.