# Sizewise

> Make sizes, amounts and big numbers feel real: to-scale lineups, fit counts and stacks. Sizewise turns numbers people cannot picture into things they can see. Line up 337 objects from atoms to galaxies at true scale, count how many of one thing fit in another, stack money as banknotes, explain any big number and see a life in weeks or a rate ticking by. Every object size comes from a cited Wikidata statement, and every view runs the same engine as the API and MCP tools.

Sizewise (Scale & big-number visualiser) is an app of usefulweb.app (https://usefulweb.app/): a full program that runs in the browser. Its engine is deterministic and the same functions are exposed as tools, so an agent can compute exactly what the app shows.

## Use it
- Landing page: https://sizewise.usefulweb.app/
- Workspace (browser app): https://sizewise.usefulweb.app/app - open a project with https://sizewise.usefulweb.app/app#project=<base64url-encoded project JSON> or a template with https://sizewise.usefulweb.app/app#template=<id>
- Project file format (JSON Schema): https://sizewise.usefulweb.app/project.schema.json
- Tutorials: https://sizewise.usefulweb.app/tutorials
- JSON API: POST https://sizewise.usefulweb.app/api/v1/tools/<toolId>/calculate (catalog: https://sizewise.usefulweb.app/api/v1/tools)
- OpenAPI: https://sizewise.usefulweb.app/openapi.json
- MCP (Streamable HTTP): https://sizewise.usefulweb.app/mcp

## Engine tools
- [Sizewise Scale Comparison](https://sizewisescalecompare.usefulweb.app/): Line up buildings, animals, planets or atoms side by side, drawn to true scale. Part of [Sizewise](https://sizewise.usefulweb.app/) (ownerApp: sizewise). API: POST https://sizewise.usefulweb.app/api/v1/tools/sizewise-scale-compare/calculate · MCP tool `sizewise_scale_compare`
- [Sizewise How Many Fit](https://sizewisefitcount.usefulweb.app/): How many Earths fit in the Sun, golf balls in a room or pallets in a trailer? Part of [Sizewise](https://sizewise.usefulweb.app/) (ownerApp: sizewise). API: POST https://sizewise.usefulweb.app/api/v1/tools/sizewise-fit-count/calculate · MCP tool `sizewise_fit_count`
- [Sizewise Big Number Explainer](https://sizewisebignumber.usefulweb.app/): What does a googol, 2^64 or 8 billion really mean? Names, digits and counting time. Part of [Sizewise](https://sizewise.usefulweb.app/) (ownerApp: sizewise). API: POST https://sizewise.usefulweb.app/api/v1/tools/sizewise-big-number/calculate · MCP tool `sizewise_big_number`
- [Sizewise Money Stack](https://sizewisemoneystack.usefulweb.app/): How tall is a million dollars? Banknotes as a stack, by weight and on pallets. Part of [Sizewise](https://sizewise.usefulweb.app/) (ownerApp: sizewise). API: POST https://sizewise.usefulweb.app/api/v1/tools/sizewise-money-stack/calculate · MCP tool `sizewise_money_stack`
- [Sizewise Life in Weeks](https://sizewiselifeweeks.usefulweb.app/): Your life as a grid of weeks: one row per year, with milestones and exact counts. Part of [Sizewise](https://sizewise.usefulweb.app/) (ownerApp: sizewise). API: POST https://sizewise.usefulweb.app/api/v1/tools/sizewise-life-weeks/calculate · MCP tool `sizewise_life_weeks`
- [Sizewise Rate Counter](https://sizewiseratecounter.usefulweb.app/): Turn “so much per year” into per second, project it, and embed a live counter. Part of [Sizewise](https://sizewise.usefulweb.app/) (ownerApp: sizewise). API: POST https://sizewise.usefulweb.app/api/v1/tools/sizewise-rate-counter/calculate · MCP tool `sizewise_rate_counter`
- [UnitProof Unit Calculator](https://unitproof.usefulweb.app/): Unit maths you can audit: dimension check, exact factors and a full derivation tree. Part of [RavingDesk](https://ravingdesk.usefulweb.app/) (ownerApp: ravingdesk). API: POST https://sizewise.usefulweb.app/api/v1/tools/unitproof/calculate · MCP tool `unitproof`

## Formats
- Import: Sizewise project (.sizewise.json), Share link (#project=), Your own objects as “Name = 1.8 m” or “Name = 40 × 30 × 20 cm”
- Export: Sizewise project (.sizewise.json), Lineup, fit plan, money stack and week grid as SVG and PNG, Lineup and number tables as CSV, Live counter as an HTML snippet, Print view, Share link

## Limits
- Many common animals, from cats to elephants, have no size in Wikidata yet, so they are not in the list; add them as your own objects.
- Each object has one size. Objects with a second or third dimension in Wikidata use it for the drawing and for area or volume; the others are drawn with typical proportions.
- Mountains are measured by their summit elevation above sea level, not their height above the surrounding land (except Mauna Kea from its base).
- Box packing tries rows in two orientations per layer; it does not search irregular mixed patterns.
- Big numbers are exact up to 20 000 digits; larger ones keep only their logarithm. Names are given in English.
- Rates are constant: no growth, seasons or time-of-day patterns.