# Graph, Dot, Isometric, Hex and Music Paper

> Printable grid, dot, isometric, hexagon, music staff and lined paper at exact sizes. Make printable paper with a square grid (with major lines), dot grid, isometric triangles, hexagons, music staves or writing lines. Spacing is exact in millimetres, the grid is centred on the page and a 10 cm scale bar lets you check the printer scale.

Part of usefulweb.app (https://usefulweb.app/). Part of [Printshop](https://printshop.usefulweb.app/) (ownerApp: printshop). Results are deterministic calculations from the inputs and the listed assumptions; the API returns exactly what the web page shows.

## Use it
- Human interface: https://printshopgraphpaper.usefulweb.app/ (interactive tool at https://printshopgraphpaper.usefulweb.app/tool)
- JSON API: POST https://printshopgraphpaper.usefulweb.app/api/v1/calculate with a JSON object of inputs (schema: https://printshopgraphpaper.usefulweb.app/api/v1/tool)
- OpenAPI: https://printshopgraphpaper.usefulweb.app/openapi.json
- MCP (Streamable HTTP): https://printshopgraphpaper.usefulweb.app/mcp - tool `printshop_graph_paper`

## Inputs
- kind (select): Paper type
- spacing (number): Spacing (mm, 0 = usual for the paper type) - Grid/dot pitch, triangle or hexagon side, line distance, or the distance between two staff lines. 0 uses 5 mm for grid and dots, 8 mm for isometric, hexagons and lined paper, 2 mm for music staves.
- majorEvery (integer): Major line every … cells
- lineWidth (number): Line width (mm)
- color (text): Line colour
- majorColor (text): Major line colour
- margin (number): Margin (mm)
- marginLine (number): Margin line for lined paper (mm from the left)
- header (boolean): Name and date line at the top
- hexOrientation (select): Hexagon orientation
- pages (integer): Pages
- paper (select): Paper size
- orientation (select): Orientation

## Method
- Square and dot grids use whole cells centred in the area inside the margin, so leftover space is split evenly. Major lines count from the first line.
- Isometric paper draws three families of lines (horizontal and ±60°) that form equilateral triangles of the given side; hexagons are regular with the given side, in offset rows (pointy top) or columns (flat top).
- Music staves have five lines with the given spacing and a gap of 1.75 staff heights between staves. Lined paper starts one line spacing below the top margin.

## Limits
- Print at 100 % (actual size) and check the 10 cm scale bar: “fit to page” changes every spacing.