Step by step

1. Choose the project unit in File > Measurement units.
2. Enter a plain number in a typed length field using that unit, or include an explicit mm/in suffix.
3. Switch units to check the same physical dimension: 25.4 mm equals 1 in.
4. Save the project to preserve its unit preference.
5. Before export, confirm its displayed unit and compare one known physical dimension after placement.

Accepted length literals

In inch mode, 1 means 25.4 mm; 1/2 means 12.7 mm; 1 1/2 means 38.1 mm. Explicit 25.4 mm displays as 1 in. Decimal points and commas and the inch quote are supported. Displayed inches are decimal; architectural feet/inches notation is not added.

Expressions and types

Geometry is stored in canonical millimetres. Formulas retain canonical semantics; Length / 2 remains the same expression and length constants inside formulas are not rewritten. Counts, angles, direction vectors, scale factors, selectors and untyped REAL values must not be treated as lengths.

Snapshots

Typed length snapshot cells follow the project unit. Selectors remain model values. Legacy cells whose types cannot be resolved retain their stored text and display model semantics.

Native export

Supported native export follows the selected unit and converts the physical boundary once. A unit switch should not resize geometry or change port direction vectors.

Imported-source limitation

Changing display units does not make an inch-authored Python source an mm-authored source. Source-native unit conversion and retained-source export have separate limitations. Do not assume arbitrary non-mm source scripts import or round-trip correctly.

Keep in mind

• Use typed dimension fields for unit-aware input. Do not add unit suffix syntax inside formulas.

Keep building