PDF export

Evolving

Print options — page size, margins, cut lines, and duplex-mirrored backs.

Export PDF sits in the preview toolbar. It prints what the preview shows, so if your code is mid-break the export uses the same last-good render you're looking at.

The button is disabled until there's at least one card to print.

The preview#

Next to the options is a picture of the actual page. It redraws as you change anything, so margins, spacing, cut lines and the mirrored back pages are all visible before you spend a render on a PDF. The arrows above it step through every page the export will contain — with duplex backs, page 2 is page 1's mirrored back.

It's drawn from the same layout the exporter uses, with the same card artwork, so it can't drift from the file you get. The one thing it can't show you is the 300 DPI rasterization: on paper the cards are images, here they're live vector art.

The options#

Option	Default	What it does
Page size	Letter (215.9 × 279.4 mm)	Or A4 (210 × 297 mm).
Backs	Duplex	How back faces are laid out — see below.
Outer margin (mm)	10	Blank border on every page. Most home printers can't print to the edge. It's a minimum: the card grid is centred left-to-right (that centring is what keeps duplex backs aligned) and starts at the top margin, so the side margins are often a little wider than you asked for.
Card spacing (mm)	0	Gap between cards. `0` means neighbours share a cut line — less cutting, no margin for error.
Cut lines	Dotted	Lines running edge to edge across the page at every card boundary. Also: off, red, bold.
Cross marks	Off	Small crop crosses at card corners only. Also: dotted, red, bold.
Print page numbers	Off	Adds plain text such as `1/10 front` or `1/10 back` immediately below the lowest card row. It never covers a card. A matching front/back pair shares its number, even in Separate mode.

Guide styles are: dotted (0.2 mm dotted black), red (0.2 mm solid, easy to see against dark art), bold (0.5 mm solid black).

Backs#

Duplex — after each page of fronts comes the matching page of backs, with columns mirrored. That's what makes a double-sided print line up when your printer flips on the long edge.
Separate — all front pages first, then all back pages. For manual re-feeding.
None — fronts only.

Cut guides are drawn on back pages too, aligned to the mirrored grid.

When Print page numbers is on, numbering counts physical card sheets rather than PDF pages. That is why matching sides say 1/10 front and 1/10 back: the label is meant to keep those two pages paired after printing. The live page preview shows the same label before export. The label is placed below the final occupied card row and is never pulled back over artwork. If the card grid reaches the bottom of the page, the label can fall outside your printer's printable area or be clipped by the PDF page; increase the outer margin if you need the label to print.

How it lays out#

Decks never share a page: each Card: block starts fresh. Within a deck, as many cards as fit inside the margins are placed row by row.

If a deck's cards can't fit even once inside the margins, the modal says so and blocks the export — reduce the margin or spacing, or choose a larger page.

Quality and errors#

Each distinct card face is rendered once at 300 DPI through the browser's own renderer, so fonts and icon ligatures come out exactly as they look in the preview, then reused everywhere it appears. A count: 10 card doesn't cost ten renders.
While exporting, a progress bar advances through card-face rendering, image embedding, page construction, and final PDF saving. Large decks can still take a while, but the current stage and percentage remain visible.
Error placeholder cards are skipped. If any exist, the modal warns you how many before you export. If every card is a placeholder there's nothing to print and export is blocked.
Images are checked before you export. When the deck uses Image shapes, the modal probes their URLs as it opens. Embedding an image into the PDF needs the host's permission (the file is fetched with crossorigin=anonymous, so the server must allow cross-origin use — CORS). Any image that can't be embedded is warned about in the modal — "N images could not be embedded" — and prints as an amber crossed-out placeholder box. The export itself is never blocked by a broken image.
Copy counts are honoured — a count: 2 card prints twice.
The file downloads as <deckname>.pdf for a single-deck project, cardgoblin.pdf otherwise.

Your option choices are remembered until you reload the page.

Not yet#

Bleed, safe zones, CMYK, and per-deck page settings aren't there yet — see the roadmap. For a professional print run, check the printer's requirements before committing.