From blank artboardto press-ready edition.

Blotter Builder is a single-screen browser editor built around a central artboard. Everything else on the screen is one of four supporting areas: the upload and layer rail, the creative tool rail, the inspector, and the canvas controls that sit over the artboard's lower edge.

Format sets the artboard's physical size and shape before you design. Blotter Builder offers three true-to-size formats — Classic square, Wide, and Hexagon — matched to physical blotter sizes, and you can switch between them at any time while working.

The artboard is the printable design surface; the stage is the darker work area that holds it and never prints. The creative tool rail is the strip of eight tools next to the artboard, and each tool changes what the inspector shows and how clicks and drags on the artboard behave.

Blotter Builder accepts JPEG, PNG, and WebP image files up to 50 MB and 50 megapixels each. A file that fails any check is added to Uploads as a visible error card rather than silently rejected, and cannot be placed until you remove it and upload a file that passes.

Place image adds an uploaded file to the artboard at its native pixel size, centered, with no scaling. Fill canvas adds it scaled and cropped to exactly match the current artboard's width and height, with no distortion. Both create a new layer and leave the original upload untouched.

Uploads offers three ways to bring content into a design without starting from your own file: Try demo artwork (a labeled sample image), Library (reusable assets, sign-in required), and Templates (procedural alignment guides). None of the three are meant to appear in a finished, ordered print.

Remove Background opens a dedicated editor for erasing part of an image — automatically or by hand — before that erased (transparent) area becomes part of your design. It works on a placed image layer or directly on an uploaded file that hasn't been placed yet.

Select picks up and moves existing layers. Pencil and Brush draw freehand strokes onto a paint layer — Pencil thin and hard-edged, Brush thicker with adjustable softness. Eraser removes part of a paint layer's content the same way you drew it. All four are in the creative tool rail.

Shape draws rectangles, ellipses, lines, and regular polygons by dragging. Pen draws a custom straight-edged path by clicking one anchor point at a time. Text places an editable text box with a single click. Each creates its own new layer — none of them merge into previous content the way paint strokes do.

The Color panel sets the color used for new paint strokes and for recoloring an existing shape, path, or text layer. Fill and Stroke are separate, independently colored targets. Colors come from a wheel, hex or numeric input, an eyedropper sampling the canvas, or saved swatches.

Creative filters apply a preset visual style — Cartoon, Sepia, Duotone, and others — to an image or paint layer, or to the whole composition. They are non-destructive: switching back to None fully restores the original look. A dedicated Pointillism preset does not currently exist in the interface — see Warnings and limits.

Layers lists every item on the artboard, top to bottom, in the same order they stack visually — top of the list renders in front. Click a layer's name to select just that layer; use its checkbox to add it to a multi-selection instead. Reordering and renaming both live in the same panel.

Duplicate copies a layer with a small position offset so you can see both. Hide toggles a layer's visibility without removing it. Lock blocks editing and moving a layer, but not deleting it. Delete removes a layer immediately, with no confirmation — undo it with `Ctrl+Z` if needed.

Transform controls a selected layer's exact width, height, position, rotation, and opacity by number, plus quick Flip H/Flip V and Rotate 90° buttons. Lock aspect ratio constrains width and height changes to whatever ratio was active when you turned it on.

Align to artboard and Distribute evenly appear in the inspector only when two or more layers are multi-selected by checkbox, and both act relative to the artboard, not the selection's own bounding box. Pattern across cells is a separate, single-layer feature that tiles an image across the artboard's perforation grid — it is powerful, replaces the original layer, and was observed to freeze the browser tab for several minutes when applied at full grid density.

Crop, in Adjust, lets you trim a placed image by dragging its corner handles, then commit with Apply crop or back out with Cancel crop. Cancel crop works cleanly. In this session's testing, completing a crop consistently produced a broken result — see Warnings and limits before using this feature on work you care about.

Four sliders in Adjust — Contrast, Black point, White point, and Gamma — tune an image layer's tonal range. All four are non-destructive: they're recomputed live from the original pixel data every time, so returning a slider to its default restores the image exactly.

Effective DPI measures how sharp a placed image will print at its current size on the artboard — calculated from the image's pixel width divided by the layer's width in inches. Below 150 DPI, the layer's Transform panel shows a red LOW badge and a resolution warning.

Blotter Builder's editor works entirely in RGB — there is no CMYK mode, toggle, or input anywhere in the interface. Print-specific color conversion happens automatically, server-side, at export time. Two separate, preview-only aids exist for judging print color on screen: Realistic view (paper texture only) and Approximate soft proof (a rough color-shift simulation) — neither is a calibrated match to the actual export.

View switches the artboard between Vector grid (thin lines marking the perforation grid) and Realistic (adds paper texture for composition judgment). Both are on-screen aids only — neither changes layer geometry, and neither is included in exported output.

Rulers, Bleed / safe zone, and custom guides are on-screen placement aids in Options. All three are excluded from exports. Rulers and Bleed / safe zone are desktop-only in practice — their checkboxes work on mobile, but the overlays never render there. Custom guides do render on mobile.

Snap to grid, in Options, pulls a layer's position to the nearest grid line (0.25 in spacing) while you drag it with the Select tool. It is checked by default. In testing, it affected dragging to reposition a layer, but not dragging a resize handle.

Undo and Redo step backward and forward through your edit history. Fit resets zoom to show the whole artboard. Recenter and Fit to frame are additional view controls that appear once there's content on the artboard. Zooming is done with `Ctrl` + scroll on the artboard.

Review production readiness, in Export, checks your design for issues that could affect printing or cutting and reports them as either blocking (must be fixed) or warnings (informational). It always reports at least two permanent placeholder warnings, since the app's grid pitch and print color profile aren't finalized yet.

Export PNG, in Export, downloads the current artboard as a single flattened PNG image. It is generated entirely in your browser — no upload or server round-trip — and downloads immediately with no confirmation dialog. Its resolution does not match the "target output resolution" quoted in Review production readiness; see Warnings and limits.

Export print PDF + cut guide, in Export, generates two paired files server-side: a print PDF and a matching SVG cut guide for Silhouette Studio. This export always gates behind a Production readiness — Export print package confirmation dialog that requires explicitly acknowledging any warnings before it proceeds, unlike Export PNG.

Create proof link and Add to cart, in Export, are the two paths from a finished design toward sharing or ordering it. Add to cart is gated behind the same acknowledge-warnings confirmation dialog as *Print PDF + Silhouette cut guide*. Proof links are unguessable, tokenized URLs managed in a per-browser list with Copy, Revoke, and Forget actions.

Blotter Builder autosaves your in-progress design to this browser automatically — no manual save action exists or is needed. On your next visit, a Recover unsaved design? dialog offers to restore it. Recovery is stored locally per device/browser (in IndexedDB), expires after 14 days, and is separate from signed-in cloud drafts.

Signing in unlocks cloud-saved drafts and a reusable artwork Library, neither of which is available as a guest. Accounts can be created with Email (email + password) or Private (no email) — a randomly-generated account identifier with no recovery path if lost. Guests can still design, export, and order without an account.

When this browser has a newer autosaved design than what's currently loaded, Blotter Builder shows the same Recover unsaved design? dialog covered in *Device recovery* — this is also the app's version-conflict mechanism. It only checks at load time. Two tabs open at once do not warn each other about conflicting edits; the last one to autosave silently wins.

Once a design is in your Cart, each line item has Quantity controls, an Edit design button, and a `⋯` menu with Duplicate and Remove. Quantity and pricing update live and correctly. Duplicate and Remove work correctly. Edit design does not — see Warnings and limits.