PDF Thumbnail Generator
Generate thumbnail images for each PDF page — for previewing, indexing, or gallery views. 5 size presets, 3 output formats (PNG/JPEG/WebP), ZIP or single-image-sprite output. 100% client-side, no uploads.
About PDF Thumbnail Generator
Generate thumbnail images for each PDF page — for previewing, indexing, or gallery views. 5 size presets, 3 output formats (PNG/JPEG/WebP), ZIP or single-image-sprite output. 100% client-side, no uploads. Everything runs locally in your browser — your data never leaves your device.
How to use
- Enter your input in the tool above.
- Adjust any options to your preference.
- Use the Copy or Download buttons to save the result.
- Everything happens locally — your data never leaves your browser.
FAQ
Are my PDFs uploaded to a server?
No. Thumbnail generation runs entirely in your browser using JavaScript. Your PDF never leaves your device, and the tool works offline.
What extra features does this tool include?
5 thumbnail size presets (128/256/512/1024/original), 3 output formats (PNG/JPEG/WebP), page-range selection, custom background color, three bundle modes (individual files, ZIP archive, or single-image sprite sheet), sprite-grid calculator, page-orientation detector, thumbnail-quality scorer, multi-format metadata reports (text/CSV/JSON), and 20-entry history with shareable URLs.
Does pdf-lib render PDF pages to images?
pdf-lib can read page dimensions, metadata, and structure but cannot rasterize page content to images. This tool generates dimension-accurate placeholder thumbnails (correct aspect ratio, page number, orientation indicator) and produces a complete metadata manifest (positions, sizes, filenames) that you can pair with a renderer like pdf.js or Ghostscript for the final raster. This keeps the tool 100% client-side with zero extra dependencies.
What is a sprite sheet?
A sprite sheet is a single image that combines all thumbnails in a grid. It's smaller and faster to load than many individual files, and is commonly used for web galleries, document previews, and PDF viewers. This tool generates the sprite layout (grid dimensions, per-thumbnail x/y coordinates) and a metadata JSON so you can render it directly in your app.
How does the page range work?
Use the same syntax as other UnQTools PDF tools: 'all', '1-3, 5, 8-10', '4-' (to end), or '-3' (from start). Invalid ranges are rejected with a clear error message.
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