Common questions
Everything you need to know about Block Poster
Block Poster supports JPG, PNG, and WebP image formats. For best results, use a high-resolution image.
No! Unlike other tools that limit you to 2.5MB or 5MB, Block Poster has no file size limit. Everything is processed locally in your browser.
No. Your images never leave your device. All processing happens 100% in your browser using the Canvas API. We never see, store, or have access to your images.
We support A4, US Letter, A3, US Legal, and Tabloid paper sizes. You can also choose between portrait and landscape orientation.
Print all pages, trim the white margins if needed, then lay them face-down on a flat surface in order. Use masking tape to join the pages together from the back. The overlap setting helps with alignment.
Yes, Block Poster is completely free with no premium tiers, no watermarks, and no ads. We believe everyone should be able to create large posters at home.
For best results, use an image that is at least 1000 pixels wide. Larger images produce better quality posters. You can also adjust the DPI setting — 150 DPI is a good balance between quality and file size.
Yes! Block Poster works on any device with a modern web browser. The interface is fully responsive and works on phones, tablets, and desktops.