DefaultToolsUnits Schema
Alias: dtu
Version: 1.0.0
This contains the unit definitions that are used by default for tools and components used across multiple iTwin applications
The DefaultToolsUnits schema provides a standardized set of unit definitions for default tools and components used across multiple iTwin applications. This schema is designed to support domain-agnostic functionality such as generic drawing tools, presentation layers, property panels, and cross-application utilities that require consistent unit measurements.
Table of contents
Kind Of Quantities
ANGLE (Default Tools Angle) KindOfQuantity 
General angular measurements for rotations and orientations
Relative Error: 0.0001
Persistence Unit: RAD
Presentation Formats
- DefaultRealU(2) [ ARC_DEG ]
- AngleDMS
AREA (Default Tools Area) KindOfQuantity
General area measurements for surface calculations
Relative Error: 0.0001
Persistence Unit: SQ_M
Presentation Formats
- DefaultRealU(2) [ SQ_M ]
- DefaultRealU(2) [ SQ_FT ]
LENGTH (Default Tools Length) KindOfQuantity
General length measurements for linear dimensions
Relative Error: 0.00001
Persistence Unit: M
Presentation Formats
- DefaultRealU(4) [ M ]
- DefaultRealU(4) [ MM ]
- AmerFI
- AmerFI(16)
- DefaultRealU(4) [ FT ]
LENGTH_COORDINATE (Default Tools Coordinate Length) KindOfQuantity
Length measurements for coordinate systems and spatial positioning
Relative Error: 0.0001
Persistence Unit: M
Presentation Formats
- DefaultRealU(4) [ KM ]
- DefaultRealU(4) [ M ]
- AmerFI
- AmerFI(16)
- DefaultRealU(4) [ FT ]
PERCENTAGE (Default Tools Percentage) KindOfQuantity
Percentage values for proportional measurements and statistics
Relative Error: 0.0001
Persistence Unit: DECIMAL_PERCENT
Presentation Formats
- DefaultRealU(2) [ PERCENT ]
- DefaultRealU(4) [ DECIMAL_PERCENT ]
TIME (Default Tools Time) KindOfQuantity
General time measurements for durations and intervals
Relative Error: 0.0001
Persistence Unit: S
Presentation Formats
- DefaultRealU(2) [ S ]
- DefaultRealU(2) [ MIN ]
- DefaultRealU(2) [ HR ]
VOLUME (Default Tools Volume) KindOfQuantity
General volume measurements for 3D space calculations
Relative Error: 0.0001
Persistence Unit: CUB_M
Presentation Formats
- DefaultRealU(2) [ CUB_M ]
- DefaultRealU(2) [ CUB_FT ]
Last Updated: 31 October, 2025