Convert Square Millimeter to Section
Convert square millimeters to sections instantly. 1 square millimeter = 3.861022e-13 section — use the live calculator, the exact formula, a conversion table and worked examples. Also check the Section to Square Millimeter converter for the reverse conversion.
Units explained
Square Millimeter
A square millimeter is a metric unit of area equal to 10⁻⁶ m² (1 mm × 1 mm). It is widely used in engineering, electronics, and small-scale technical work.
Derived by squaring the millimeter, defined as 1/1000 of a meter. The milli- prefix comes from the Latin 'mille' (thousand).
Square millimeters express PCB trace cross-sections, the area of small mechanical features in CAD drawings, biological sample sizes, and material thicknesses.
Millimeter has been part of the metric system since 1795.
Section
A section is a unit of area used in the US Public Land Survey System, equal to 1 square mile (640 acres or approximately 2.59 km²).
Defined by the Land Ordinance of 1785 as 1/36 of a township. Sections are numbered 1-36 within each township.
Sections are the fundamental unit of US public land records in PLSS states (essentially the central and western US). Property descriptions like 'NE quarter of section 14, township 3 north, range 2 east' use this system.
Defined by the US Land Ordinance of 1785.
Square Millimeter to Section conversion formula
The relationship between square millimeters and sections:
To convert square millimeters to sections, multiply the value in square millimeters by 3.861022e-13. To reverse, multiply sections by 2.589988e+12.
How to use this converter
Type a value into the calculator. The result in sections updates as you type. Tap a quick value, copy the result with one click, or use the swap arrow to jump straight to the Section to Square Millimeter converter for the reverse direction.
Step-by-step: convert square millimeters to sections
- Write down the value in square millimeters (mm²).
- Multiply that value by the factor 3.861022e-13.
- The product is the equivalent value in sections (sec).
- To reverse, multiply the section value by 2.589988e+12.
Worked examples
Example 1 — Convert 1 mm² to sec:
1 × 3.861022e-13 = 3.861022e-13 sec
Example 2 — Convert 100 mm² to sec:
100 × 3.861022e-13 = 3.861022e-11 sec
Real-world example — Plastic-film thickness alternates
A 150-square millimeter plastic film converts cleanly to sections — useful for packaging buyers reconciling supplier datasheets across metric and US measurement systems.
150 mm² × 3.861022e-13 = 5.791532e-11 sec
Real-world example — Hair-width scale measurements
A 70-square millimeter measurement (about the diameter of a human hair) is the kind of value materials engineers regularly express in adjacent micro-scale units like sections for direct comparison across supplier datasheets.
70 mm² × 3.861022e-13 = 2.702715e-11 sec
Real-world example — Paper and film thicknesses
At the thickness of office paper (roughly 3 square millimeters), converting between sub-millimeter units is routine for packaging and printing buyers comparing quotes from metric and US suppliers.
3 mm² × 3.861022e-13 = 1.158306e-12 sec
Square Millimeter to Section conversion table
Standard reference values for converting square millimeters to sections:
| Square Millimeter [mm²] | Section [sec] |
|---|---|
| 0.01 | 3.861022e-15 |
| 0.1 | 3.861022e-14 |
| 1 | 3.861022e-13 |
| 2 | 7.722043e-13 |
| 3 | 1.158306e-12 |
| 4 | 1.544409e-12 |
| 5 | 1.930511e-12 |
| 10 | 3.861022e-12 |
| 20 | 7.722043e-12 |
| 30 | 1.158306e-11 |
| 40 | 1.544409e-11 |
| 50 | 1.930511e-11 |
| 100 | 3.861022e-11 |
| 500 | 1.930511e-10 |
| 1000 | 3.861022e-10 |
Frequently asked questions
How many sections is 1 square millimeter?
How do I convert square millimeters to sections?
How do I convert sections back to square millimeters?
How many sections is 100 square millimeters?
Popular area unit conversions
Convert Square Millimeter to other area units
Show all Square Millimeter conversions
Metric / SI (15 units)
Imperial / US Customary (15 units)
US Survey (5 units)
Indian Subcontinent (16 units)
Other Regional (10 units)
Scientific / Physics (5 units)
Sources & references
Conversion factor (1 mm² = 3.861022e-13 sec) 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.