Tool
Poster split calculator
Print a large poster on a normal home printer. Pick the target size and this page works out the tile grid and sheet count — then drop in an image or PDF and it generates the print-ready tiled PDF with cut marks and alignment guides, entirely in your browser. Nothing is uploaded.
Result
12 sheets
- Grid
- 4 × 3
- Tile orientation
- portrait
- Printable per tile
- 200 × 287 mm
- Coverage per inner tile
- 190 × 277 mm
Tiling preview
Dashed lines are tile joints. Each joint hides a 10 mm overlap.
Generate the tiled PDF
Choose an image (PNG, JPG, WebP) or a PDF. It is processed on your device — the file never leaves your browser. Output: one PDF with 12 A4 pages, each at true scale with cut marks and alignment guides.
Assembly in four steps
1 · Print at 100 %
Print the generated PDF with scale at 100 % ("Actual size", never "Fit"). Verify the first sheet with a ruler before printing the rest.
2 · Trim at the cut marks
On every tile except the left column, trim the left margin at the corner ticks. Same for the top margin on every row except the first.
3 · Align on the dashed guides
Lay each trimmed edge onto its neighbour so it sits on the printed dashed line — the artwork in the overlap strip lines up seamlessly.
4 · Tape from the back
Hold each joint with small tape tabs first, check alignment from the front, then run full-length tape along every joint on the back.
Frequently asked questions
Is my file uploaded anywhere?
No. The image or PDF is opened directly in your browser with the FileReader and canvas APIs; splitting and PDF generation happen on your device. Nothing is transmitted to a server — the site has no backend to send it to.
How does poster tiling work?
The poster is divided into a grid of tiles, each printed on a normal sheet (A4 or Letter) with a small overlap between neighbouring tiles. After printing, you trim the overlap off one edge of each inner tile, align the sheets using the printed guides and join them with tape from the back.
Why do I need an overlap?
Home printers cannot print to the paper edge and cutting is never perfectly straight. The overlap (10 mm by default) duplicates a strip of the artwork on both neighbouring tiles, so small trimming errors disappear inside the joint instead of leaving white gaps.
What do the marks on each generated page mean?
Short corner ticks show where to cut (the left edge of every column after the first, the top edge of every row after the first). The light dashed line shows where the edge of the next sheet should sit when you glue or tape the overlap. A small label in the margin identifies each tile's row and column.
What DPI should I choose?
150 DPI is the large-format standard and the right default: posters are viewed from a distance. Choose 300 DPI only for small posters (A3/A2) that will be inspected up close — file size roughly quadruples. 96 DPI is a quick draft for checking the layout.
My source is a PDF — does the output stay vector?
No — each tile is rendered to a high-resolution raster at your chosen DPI, because that is the only way to slice arbitrary content reliably in the browser. At 150–300 DPI the printed result is visually indistinguishable from vector for poster viewing distances.
Does the calculator account for scaling?
The generated PDF is always at true scale: each page is exactly A4 or Letter, so print it at 100% ("Actual size") with scaling off. If you use the grid numbers with your own PDF reader's poster mode instead, the same rule applies.
What is the best overlap value?
10 mm suits most home printers. If your printer has unusually wide unprintable margins (some are 5 mm or more per edge), raise the overlap to 15 mm so alignment stays easy.