Smart Compress illustration

Smart Compress

Shrink your PDF with AI-enhanced image compression that runs entirely in your browser. Photos are denoised and re-encoded while text and vectors stay pixel-perfect. No upload, no signup.

How to Smart-Compress a PDF in Your Browser

  1. 1

    Upload your PDF

    Drag and drop a photo-heavy PDF into the upload area, or click to browse. Your file never leaves your device — everything runs in your browser.

  2. 2

    Pick an intensity

    Choose Light to preserve maximum detail, Balanced for the best size-to-quality trade-off, or Aggressive for the smallest file possible. Balanced works for most documents.

  3. 3

    Click Smart Compress

    On first use, your browser downloads a small AI upscaler model (about 5–15 MB) and caches it locally. Subsequent runs are instant. Smart Compress then enhances each image and re-encodes them with tight perceptual loss.

  4. 4

    Download the smaller PDF

    Save the compressed file. Text and vector graphics are pixel-perfect — only the embedded photos were touched. The original PDF on your device is untouched.

What Makes Smart Compress Different?

Smart Compress is the only PDF compressor that runs entirely on your device while still using AI to recover image quality. The pipeline extracts each embedded photo, denoises it with a Real-ESRGAN-style super-resolution model, downscales it to display resolution, then re-encodes it as a tight JPEG — and writes it back into the PDF in place. Text, fonts, and vector shapes are never touched, so headlines and body copy stay perfectly sharp. Because everything runs locally via WebGPU (with a WebAssembly fallback for older browsers), nothing is ever uploaded to a server. There's no signup, no file-size limit imposed by a hosted backend, and no privacy risk. Smart Compress is best for photo-heavy documents like portfolios, scanned reports, real-estate listings, marketing decks, and travel itineraries — anywhere you want a smaller file without losing the look of the photos.

Frequently Asked Questions

Does this really run in my browser without uploading?

Yes. Smart Compress is a client-side tool — your PDF never leaves your device. The AI model is downloaded once and cached locally in your browser's storage, then runs on your CPU or GPU. You can verify by opening DevTools → Network and watching: only the model file is fetched, never your PDF.

Why is the first run slower than the second?

On first use, your browser downloads a ~5–15 MB AI upscaler model and stores it locally. Every run after that uses the cached copy, so subsequent compressions start instantly. The model only re-downloads if you clear your browser storage.

Will Smart Compress make my text look blurry?

No. Smart Compress only touches embedded raster images (photos and scans). Text, fonts, vector graphics, tables, and form fields are never re-encoded — they stay pixel-perfect. This is the main reason Smart Compress is a separate tool from Compress PDF, which can rasterize entire pages.

Which browsers support Smart Compress?

Smart Compress works in any modern browser. For the fastest experience, use a WebGPU-capable browser like Chrome 121+, Edge 121+, or Safari 18.1+ on macOS. Browsers without WebGPU (older versions, Firefox on some platforms, iOS Safari with bugs) automatically fall back to a slower WebAssembly path. The badge in the tool tells you which mode is active.

What kinds of PDFs benefit most?

Photo-heavy PDFs see the biggest savings: portfolios, scanned documents, real-estate brochures, travel itineraries, marketing decks, and reports with chart screenshots or product photos. Text-only PDFs and PDFs whose images are stored as Flate-encoded raw pixels (common in some Word-to-PDF exports) won't shrink much in v1 — try the regular Compress PDF tool for those.

Why is there an image cap on some browsers?

On browsers without WebGPU, AI inference runs on the CPU through WebAssembly, which is significantly slower. To prevent your browser from freezing on PDFs with dozens of images, Smart Compress caps WebAssembly mode at 20 images. If your PDF exceeds that, we'll suggest the regular Compress PDF tool instead.

Is Smart Compress really free?

Yes. There's no signup, no payment, no usage cap. Because all the AI inference runs on your device, there are no server costs to recoup, and we never plan to add a paywall to this tool.