Secure your PDF with strong password protection and encryption.
Reduce file size without losing quality.
Low‑resolution images ruin the quality of your PDFs – pixelated photos, blurry product shots, and graphics that print poorly. Our AI‑powered tool increases image resolution inside any PDF using super‑resolution technology. Boost DPI from 72 to 300, from 150 to 600, without losing detail. Perfect for print‑ready catalogues, professional portfolios, and archival documents. Free trial, no signup required.
Did you know? A 150 DPI image printed at 300 DPI loses over 75% of its sharpness. AI upscaling recovers that detail, making your PDFs print‑ready.
Old scans were often saved at low resolution. Upscale to 300 DPI for printing.
Images saved for web (72 DPI) look terrible in print. AI upscaling fixes that.
Tiny images can be enlarged 2‑4x without pixelation using super‑resolution.
Recover print‑ready quality from low‑res PDFs when the source files are lost.
Bonus – large‑format printing: Posters and banners need 300‑600 DPI. Our tool prepares your PDFs for any print size.
Upload your PDF – The tool detects the current DPI of each image.
Select target DPI or scale factor – Choose 300 DPI for print, 600 DPI for archival, or 2x/3x/4x upscale.
Apply AI super‑resolution – The tool adds pixels and reconstructs detail. Preview before/after.
Optionally compress – Use smart compression to reduce file size without losing upscaled detail.
Download the high‑resolution PDF – Ready for print or professional use.
Pro Tip: For mixed content (text + images), use selective upscaling – only upscale image regions, leave text pages unchanged to save file size.
Our AI model was trained on millions of low‑res / high‑res image pairs. It learns to “guess” what the original high‑resolution image should look like, adding detail where none existed before.
Choosing the right DPI saves file size and ensures quality:
Upscaling increases file size, but you can minimise the impact:
With these techniques, a 5 MB PDF can become 12‑15 MB after upscaling to 300 DPI – still acceptable for email and most portals.
Tip: If you have a very large PDF, first compress it with our tool, then upscale only the images you need.
⚡ Need to adjust or standardise DPI without changing pixels?
Use our dedicated PDF DPI Changer to view, adjust, or unify the DPI metadata of embedded images. Perfect for pre‑press compliance, print workflow validation, and preparing files for commercial printing without altering visual quality.
Yes. Our AI super‑resolution tool analyses each image and adds new pixels to increase DPI (e.g., from 150 to 300). It reconstructs missing detail, making images print‑ready without the original source files.
You can upscale images by 2x, 3x, or 4x. For example, a 150 DPI image can be boosted to 300 DPI, 450 DPI, or 600 DPI. The tool also lets you set a target DPI directly (e.g., 300 DPI).
Yes, because adding pixels increases file size. A 2x upscale (to 300 DPI) typically increases size by 2‑3x. However, our smart compression (JPEG2000) can reduce the overhead by up to 70% while preserving quality.
Traditional upscaling (bicubic, Lanczos) simply stretches pixels, causing blur. AI super‑resolution adds realistic detail by learning from millions of high‑resolution images. The result is a sharp, natural‑looking image that often rivals a native high‑res original.
Photos, product shots, scanned artwork, and any image that will be printed benefits the most. Text‑heavy images also improve, but vector text is already sharp – we recommend upscaling only raster images.
Yes. TLS 1.3 encryption, auto‑deletion within 24 hours. An offline desktop version is available for organisations with strict privacy policies.
The online tool processes one file at a time. For batch processing, use our desktop application (paid).
For on‑screen viewing (web, email), 150 DPI is sufficient. For office printing, 200‑250 DPI works. For professional printing (brochures, magazines), 300 DPI is recommended. For archival/fine art, 600 DPI.
Upload your PDF and let AI upscale every image to print‑ready resolution – free trial, no signup.
Enhancing a PDF improves visual clarity by adjusting resolution, sharpening text edges, and increasing contrast between foreground and background elements. This process is particularly useful for scanned documents, blurry text, or faded paperwork.
Several factors may reduce the readability of a PDF document. Low-resolution scanning, aggressive compression, improper export settings, and camera-captured documents can all introduce blur or reduce contrast.
Modern PDF enhancement tools apply multiple processing techniques to improve readability.
PDF enhancement algorithms work by analyzing pixel density and grayscale distribution. Contrast adjustment increases the difference between text and background while sharpening filters reconstruct blurred edges. When combined with OCR preparation, enhancement dramatically improves machine readability.
Explore the full collection of tools in the PDF Enhancement Guide.