Each Stone Calculator tool is intended to answer a defined estimating question. The calculator page is the source of truth for that tool: it identifies the task, required inputs, units, method, outputs, and limitations. This page explains how to read and use that information.
1. Start with the task
Choose a tool whose stated purpose matches the question you need to answer. Similar-sounding estimates can use different models. For example, a measured surface area is not the same as a cutting layout, usable slab yield, installed quantity, supplier order, or structural design.
2. Enter project and product data
Use dimensions from the actual project and product values from the relevant manufacturer or supplier documentation. Read each field label, help text, unit, required state, and allowed range. If a tool offers unit selection or conversion, use the displayed selection and confirm the final unit shown with every result. Do not substitute an assumed density, coverage rate, package size, yield, allowance, or price for product-specific information unless the page explicitly identifies that value and its basis.
3. Understand the calculation
The calculation follows the method configured for that individual tool. Depending on the task, it may use a formula, a sequence of steps, a lookup table, or a defined algorithm. Unit conversions, rounding, conditional inputs, and intermediate values can affect the displayed result. The calculator page should identify material assumptions and the source basis where one is relevant. No single formula or allowance applies to every natural-stone product or project.
4. Read outputs with their limits
Output labels and units describe what the model calculated; they do not automatically describe a final purchase quantity or a guaranteed project outcome. Validation limits are checks on acceptable inputs. They are not necessarily recommendations, tolerances, code limits, or manufacturer limits. A value accepted by a form is not proof that it is appropriate for your project.
5. Verify consequential decisions
Compare important results with drawings, templates, current product data, supplier packaging, and the instructions of the manufacturer or qualified professional responsible for the work. Natural stone can vary in dimensions, density, finish, defects, and usable yield. A calculator does not inspect a slab, determine a fabrication layout, account for every site condition, or certify an installation.
Sources and revisions
Where a tool depends on an external specification, dataset, or product value, its page should identify the relevant source and explain what that source supports. A source may support one input or method without supporting every assumption or result. Standards references do not by themselves make a calculation a compliance check. When a method changes, the affected tool page is the place to review its current inputs, release, sources, and limitations.
See the current calculator directory, the Guides archive, and the disclosure.