METHODS & QUALITY

Useful starts with clear.

A calculator should explain what it means, not just display a number.

What is available?

The private preview contains 1010 available tools and 100 implementation drafts awaiting specialist review. Some first versions deliberately support a narrower scope than the original roadmap; their input labels and assumptions describe the implemented scope.

How we check

Deterministic tools are checked against reference example outputs. The development batches check every default output and every output in a separately worked changed-input scenario. Earlier tools retain primary-output references and selected secondary-output checks. Core maths also receives additional edge and property checks. Browser checks cover page loading, input errors, small screens, search, favourites and sharing. This is software verification, not independent expert certification.

View the machine-readable test report

How this is calculated

All 1110 implemented pages have a method for every output, defined input symbols and units, and a complete example result table where the output is deterministic. Simple formulas are taken from the calculator definitions. Conditional rules and algorithms have explicit explanations. Unknown formula notation or an undocumented output stops the site build. The additional planned calculators are drafts, not verified implementations.

These explanations document the implemented behaviour. Software checks do not establish that every specialist model is appropriate for every use; the existing review holds still apply.

Visual explanations

20 tools include interactive visual explanations covering savings, borrowing, household budgets and material quantities. Inspect chart points, compare saved inputs, or use the data table. Saved comparisons stay in memory for this page and are cleared on reset or reload; shared links include only the current calculator inputs. Material bars explain quantities, not physical cutting layouts.

• Discount and sale price
• Tip and bill split
• Compound interest
• Simple interest
• Inflation-adjusted money
• Future value of a lump sum
• Savings contribution growth
• Emergency fund target
• Subscription spending
• Investment fee impact
• Loan repayment
• Mortgage deposit
• Break-even units
• Wall paint quantity
• Flooring packs
• Tile quantity
• Tile adhesive quantity
• Plaster quantity
• Renovation contingency budget
• Turf rolls

Tool registry and question finder

The machine-readable registry maps 3,000 planned tools: 1010 available, 100 held, and 1890 not yet implemented. It records implementation versions, inputs, output descriptions, methods and availability. The full finder registry covers every available tool, including variable text outputs and interactive draws. The full finder registry describes labelled forms separately; unknown physical units are not invented.

Try the 1010-tool question finder. 50 tools retain their original unit-specific contracts and approved conversions. The remaining available calculators use labelled forms with typed numeric, list or text inputs, original calculator validation and no automatic conversions. Random tools generate a result only when a visitor presses the draw button. The finder uses GPT-6 Luna to select a tool and extract explicit numbers, asks for missing information, and prepares a form for user review. Server validation rejects held and unbuilt tools, unknown fields, missing source evidence and invalid values. A bounded search selects the relevant calculator definitions before asking the model to prepare a form. A few length and area conversions are explicit; chained calculations and live rates are not supported. Local phrase matching is an optional fallback. See the integration contract.

Domain review

Statistics, physics, electronics and chemistry stay in the review queue. Financial pages are illustrative arithmetic with user-entered assumptions, not current rates or personalised advice. Materials pages estimate quantities; they do not approve structural designs or building-code compliance.

Editorial approach

Each page explains its inputs, gives an example and states its method. Example figures are coupled to the implemented calculation and checked against separate fixtures. There is no fabricated expert author or review badge. Broader source-by-source editorial review remains a public-launch requirement.

Build provenance

Built with coding assistance in this workspace. Qwen and Strata were not used for this release; Strata remains stopped. GPT-6 Luna is invoked only when visitors submit questions to the AI finder. Ordinary calculator results still run through browser code.