Why a small depth error can dominate a volume estimate.
Which measured dimension contributes the largest relative volume uncertainty?
Use the matching calculator
Use this decision sequence
- Record the measured dimensions and their own stated uncertainty bounds.
- Compare each absolute error with its corresponding dimension.
- Calculate lower and upper products rather than adding unlike length errors together.
- Keep this geometric range separate from product loss and supplier rounding.
Keep the quantities distinct
| Quantity or assumption | How to use it |
|---|---|
| Absolute error | A distance in its own dimension. |
| Relative error | Error divided by that dimension. |
| Order allowance | A purchasing decision, not a measurement confidence interval. |
Worked comparison
A 4 m by 3 m by 0.1 m component has nominal volume 1.2 m³. Bounds of ±0.1 m on each plan dimension and ±0.01 m on depth give a lower product 3.9×2.9×0.09 = 1.0179 m³ and upper product 4.1×3.1×0.11 = 1.3981 m³. The depth bound alone is 10% of nominal depth.
Check before using the estimate
Worst-case endpoints do not assign probabilities or justify choosing a design thickness.
All dimensions, product properties, prices and specifications in this example are illustrative arithmetic inputs. Use the values from your measured plan, selected product data sheet and supplier quote. This guide does not choose construction specifications or certify safety.
Calculation and scope checked 2026-10-04. Methods and scope.
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