BlockPoster.ai Pro

BlockPoster.ai is a browser-based tool for turning a single image into a large poster printed across ordinary sheets of paper. Visitors upload a photo or generate artwork with AI, then crop, split and preview the layout before downloading a PDF. It is aimed at people with a home printer who want wall-sized art, classroom displays or event decorations without a print shop.

What is BlockPoster.ai?

BlockPoster.ai splits one image into a grid of pages that can be printed on a standard printer and assembled into a larger picture. The site walks through four steps: start your block poster, size your block poster, review your block poster set, and check the print page preview. Images can be dropped in or browsed for as JPG, PNG, WebP or PDF files up to 40 MB each, or imported from an image link. The site states that photos stay on the user's device.

Sizing options include paper size (A4, US Letter, A3, US Legal and Tabloid), orientation, poster width in pages, fit or fill behaviour, margins and overlap. A live preview shows the page grid, finished size and effective DPI, and the last sheet can be checked for margins, guides and overlap before download. A free printer calibration page with rulers and a square is offered for checking output at 100 percent.

Key features

• Image to block poster: Converts a photo or AI-generated image into a multi-page PDF grid, with page 1 of the PDF serving as the assembly guide.
• AI image creation: A "Create with AI" option lets users generate artwork inside the tool instead of uploading a file.
• Paper and layout controls: Paper size, orientation, pages wide, auto height, fit or fill, margin and overlap settings, with centimetres or inches.
• Print preview: Shows dashed overlap lines, corner trim marks and alignment crosshairs, plus finished size, total pages and effective DPI.
• Resolution guidance: Displays source and crop dimensions with estimated artwork sizes at 150 and 300 DPI, and warns when large prints may look blurry.
• Batch processing: Multiple images can be added to a set, each keeping its own crop, with shared print settings and reusable presets.
• Calibration page: A free test sheet with a 100 mm ruler, 4 inch ruler and 50 mm square to verify printer scaling.

Pricing

The site publishes a free tier and a paid upgrade rather than a pricing table. The free basic PDF is limited to 150 DPI, carries a brand watermark and requires no sign-in. Only the first file in a set is available on the free tier. Paid plans unlock HD, watermark-free downloads and batch export. The site does not publish prices; it directs users to its pricing page, and downloads are stated not to use AI credits.

FAQ

Do I need an account to make a poster?

The free basic PDF can be downloaded without signing in. The site also offers sign-in and a My projects area for saving work, and batch export requires an upgrade rather than an account alone.

What file types and sizes can I upload?

The upload area accepts JPG, PNG, WebP or PDF files up to 40 MB each, and images can also be imported from a link. The site states that uploaded photos stay on the user's device.

How do I get the best print result?

The site advises printing at Actual size or 100 percent rather than Fit to page, printing one test sheet first, then trimming, aligning and taping sheets from the back. A free calibration page is available for checking scale.