OptiDrop

Compress PDF Files Online — Reduce Size, Keep Quality

Reduce the file size of your PDF documents while preserving quality. Choose from High, Medium, or Low compression. Everything runs in your browser — your files never leave your device.

Drop a PDF File Here or Tap to Browse

Supports PDF files up to 100MB

No upload — your PDF stays on your device.
100% Local — your file never leaves this device

What to do next →

Extract pages as images

Convert PDF pages to individual JPG images for editing or sharing.

Merge images into PDF

Combine multiple images into a single PDF document.

Compress PDF Files Online — Free, No Upload Required

OptiDrop's PDF Compressor is a free online tool that reduces the file size of your PDF documents while preserving visual quality. Whether you need to compress a PDF for email attachment limits, upload it to a government portal, or simply save storage space, our tool delivers fast and effective results. Unlike other online compressors, OptiDrop processes everything locally in your browser — your PDFs are never uploaded to any server, making it completely safe for confidential documents like contracts, invoices, and academic papers.

How PDF Compression Works

Our tool uses PDF.js to read each page of your PDF, renders it to a canvas, and then recompresses the images using JPEG encoding at your chosen quality level. It then uses jsPDF to reassemble the pages into a new, smaller PDF. This approach is particularly effective for scanned documents and PDFs with large embedded images, often achieving 30-70% size reduction.

Three Quality Levels for Every Need

Choose High quality for documents where visual fidelity matters most — the difference is barely noticeable. Medium offers a great balance between size and quality for everyday use. Low produces the smallest files, ideal for email attachments or when file size limits are strict. All three settings keep text readable and sharp.

Frequently Asked Questions

Depending on the content and quality settings, you can typically reduce a PDF file size by 30-70%. Scanned PDFs with large images compress the most, while text-heavy PDFs may see smaller reductions.
At the High quality setting, the visual difference is minimal and barely noticeable. Medium and Low settings trade some quality for smaller file sizes. Text remains crisp at all settings; only embedded images are recompressed.
OptiDrop can handle PDFs up to 100MB. Since all processing happens in your browser, the actual limit depends on your device memory. Most modern devices handle files up to 100MB without issues.
Absolutely. Your PDF never leaves your device. All compression is done locally in your browser using JavaScript. No data is uploaded to any server, making it completely safe for confidential documents.
Yes. Scanned PDFs typically contain large images that compress very well. Our tool recompresses the images within the PDF while preserving the document structure, often achieving significant size reductions on scanned documents.

PDF Compressor — About This Tool

OptiDrop PDF Compressor reduces the file size of your PDF documents while preserving visual quality. It is perfect for compressing scanned documents, academic papers, and reports so they meet email attachment limits or government portal upload restrictions. Choose from High, Medium, or Low compression levels depending on your needs. All processing happens locally in your browser — your PDF is never uploaded to any server, making it safe for confidential documents like contracts, invoices, and financial records.

How to Use PDF Compressor

  1. Drop your PDF file into the upload zone or tap to browse. Files up to 100MB are supported.
  2. Choose your compression level: High (best quality, moderate reduction), Medium (balanced), or Low (smallest file size).
  3. Click Compress PDF and watch the progress bar as each page is recompressed locally in your browser.
  4. View the before/after size comparison and download your compressed PDF instantly.

Frequently Asked Questions

Will compressing my PDF reduce its quality?

At the High quality setting, the visual difference is minimal and barely noticeable even when comparing side by side. Text remains crisp and readable at all compression levels — only embedded images within the PDF are recompressed. Medium offers a great balance between size reduction and visual quality for everyday use. Low produces the smallest files and is ideal for email attachments where file size limits are strict. For example, a scanned 20-page contract at High quality typically shrinks by 30-50% while remaining perfectly legible.

What is the maximum PDF file size I can compress?

OptiDrop can handle PDFs up to 100MB. Since all compression happens in your browser using JavaScript, the actual practical limit depends on your device's available memory. Most modern smartphones, tablets, and computers handle files up to 100MB without issues. If your browser struggles with a very large file, try closing other tabs to free up memory. There is no daily limit on how many PDFs you can compress — the tool is completely free with no hidden restrictions.

Does this work well for scanned PDFs?

Yes, scanned PDFs are actually the best candidates for compression because they typically contain large, uncompressed or lightly compressed images of each scanned page. OptiDrop recompresses these embedded images using JPEG encoding at your chosen quality level, often achieving 40-70% size reduction on scanned documents. The text on scanned pages remains readable, and the overall document structure is preserved. This is especially useful when you need to email a multi-page scanned contract or upload scanned certificates to a government portal with strict file size limits.

Is my PDF file kept private and secure?

Absolutely. Your PDF never leaves your device at any point during the compression process. OptiDrop reads your file using the browser's built-in JavaScript APIs, renders each page to a canvas, recompresses the images, and assembles a new PDF — all locally on your machine. No data is transmitted to any external server, no cloud processing is involved, and no copies of your document are stored anywhere outside your browser's temporary memory. This makes it completely safe for compressing confidential documents like financial statements, legal contracts, medical records, and government forms.