Site Layout Diagonal 3-4-5 Calculator
Scaled3–4–5right angle layout diagonal5s, not survey-proof or carpenter angle from arbitrary legs. Actual independently established design/material/calibration and matched units; not a safe work instruction, code compliance or engineering approval.
Description
A 3:4:5 triangle has a right angle between its two shorter sides and can support layout checks.
A 3:4:5 triangle has a right angle between its two shorter sides and can support layout checks.1
This tool returns the diagonal for a supplied scale when the intended legs are three and four times that scale.
When to use Site Layout Diagonal 3-4-5 Calculator
Use this tool to obtain the diagonal for a supplied scale when the intended legs are three and four times that scale.
How to use Site Layout Diagonal 3-4-5 Calculator and how it works
- Prepare actualThreeFourFiveScale, with the units, conventions and assumptions below.
- Enter the required fields and run Site Layout Diagonal 3-4-5 Calculator.
- Read result.value using the output definitions below.
- Correct any rejected inputs and rerun; interpret the result within the stated model and its assumptions.
| Input field | Meaning | Value type | Requirement |
|---|---|---|---|
| actualThreeFourFiveScale | Actual Three Four Five Scale. Use the units and matching context stated in the calculation below. | number | Required; strictly positive; finite; other constraints below |
Supply a strictly positive scale in a chosen length unit. Return 5*scale as the diagonal for intended legs 3*scale and 4*scale. The tool does not accept arbitrary measured legs or verify a laid-out corner is square.
diagonal=5*scale Apply the input ordering, units and branch conditions stated above.
| Output field | Meaning | Value type |
|---|---|---|
| result | Object containing the calculated or selected fields below. | object |
| result.value | Conditional geometric length in the input's compatible length unit. | number |
{
"input": {
"actualThreeFourFiveScale": 2
},
"output": {
"result": {
"value": 10
}
}
}Limitations and assumptions
The calculation uses the supplied observations and model inputs. It does not collect measurements, select a reference population or coefficient, or establish that the model applies to the actual case. The stated branch conditions and output units remain part of the result.
All fields require explicit values. Unexpected fields, wrong types, nonfinite numbers and sparse arrays are rejected. Alignment, bounds and supported-token rules are explained above; extremely large inputs or nonfinite results can also fail. Input errors differ from successful false comparisons, unavailable-domain flags and empty match lists.
Alternative or Complementary methods
Use Fence Post Spacing Calculator for a complementary operation: A fence run divided into equal bays has a center-to-center spacing determined by its length and number of bays.
Use Batter Boards Offset Calculator for a complementary operation: Batter boards carry layout lines outside the excavation so their positions can survive earthwork.
References
-
Site Layout Diagonal 3-4-5 Calculator — tool.io
Similar or alternative tools
- Fence Post Spacing Calculator
A fence run divided into equal bays has a center-to-center spacing determined by its length and number of bays.
- Batter Boards Offset Calculator
Batter boards carry layout lines outside the excavation so their positions can survive earthwork.