Length · Unit Converter

Convert Section to Square Millimeter

Convert sections to square millimeters instantly. 1 section = 2.589988e+12 square millimeter — use the live calculator, the exact formula, a conversion table and worked examples. Also check the Square Millimeter to Section converter for the reverse conversion.

Written by Sunith Babu L, Ph.D., Lead Engineer Reviewed by Girish V Kulkarni Ph.D.
Length category 2 min read Published Last reviewed Updated

Units explained

US Survey

Section

What is a 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).

Origin of the section

Defined by the Land Ordinance of 1785 as 1/36 of a township. Sections are numbered 1-36 within each township.

Where it is used

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.

When and where it was developed

Defined by the US Land Ordinance of 1785.

Metric / SI

Square Millimeter

What is a 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.

Origin of the square millimeter

Derived by squaring the millimeter, defined as 1/1000 of a meter. The milli- prefix comes from the Latin 'mille' (thousand).

Where it is used

Square millimeters express PCB trace cross-sections, the area of small mechanical features in CAD drawings, biological sample sizes, and material thicknesses.

When and where it was developed

Millimeter has been part of the metric system since 1795.

Section to Square Millimeter conversion formula

The relationship between sections and square millimeters:

1 sec = 2.589988e+12 mm²
1 mm² = 3.861022e-13 sec

To convert sections to square millimeters, multiply the value in sections by 2.589988e+12. To reverse, multiply square millimeters by 3.861022e-13.

How to use this converter

Type a value into the calculator. The result in square millimeters 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 Millimeter to Section converter for the reverse direction.

Step-by-step: convert sections to square millimeters

  1. Write down the value in sections (sec).
  2. Multiply that value by the factor 2.589988e+12.
  3. The product is the equivalent value in square millimeters (mm²).
  4. To reverse, multiply the square millimeter value by 3.861022e-13.

Worked examples

Example 1 — Convert 1 sec to mm²:
1 × 2.589988e+12 = 2.589988e+12 mm²

Example 2 — Convert 100 sec to mm²:
100 × 2.589988e+12 = 2.589988e+14 mm²

Section to Square Millimeter conversion table

Standard reference values for converting sections to square millimeters:

Section [sec]Square Millimeter [mm²]
0.012.589988e+10
0.12.589988e+11
12.589988e+12
25.179976e+12
37.769964e+12
41.035995e+13
51.294994e+13
102.589988e+13
205.179976e+13
307.769964e+13
401.035995e+14
501.294994e+14
1002.589988e+14
5001.294994e+15
10002.589988e+15

Frequently asked questions

How many square millimeters is 1 section?
1 section equals 2.589988e+12 square millimeter.
How do I convert sections to square millimeters?
Multiply the value in sections by 2.589988e+12 to get square millimeters.
How do I convert square millimeters back to sections?
Multiply the value in square millimeters by 3.861022e-13, or use the Square Millimeter to Section converter.
How many square millimeters is 100 sections?
100 sections equals 2.589988e+14 square millimeters, because 100 × 2.589988e+12 = 2.589988e+14.

Convert Section to other area units

Show all Section conversions

Sources & references

Conversion factor (1 sec = 2.589988e+12 mm²) verified against the following authoritative sources:

Results are provided for general reference. Verify critical measurements against an authoritative standard.