Compress PDF

Drag and drop PDF here • One file at a time • Original file unchanged

PDF Tools

PDF Compressor Online

Compress PDF files online for free. Reduce PDF size for email, document uploads, forms, portals, WhatsApp and sharing with fast browser-based processing, grayscale mode and adjustable compression settings.

Browser-basedFree PDF reducerNo signupAdjustable qualityOriginal unchanged

How to compress a PDF online

Upload PDF

Select or drag and drop the PDF file you want to compress.

Choose compression mode

Pick light, balanced, strong or custom compression depending on your quality and file size requirement.

Use grayscale if needed

Enable grayscale for scanned documents or black-and-white files when you need a smaller PDF.

Set output file name

Optionally rename the compressed PDF before downloading.

Compress and download

Click Compress PDF and download the reduced-size PDF file.

Start with Balanced Compression for normal office PDFs, reports and scanned documents. Use Strong Compression when the PDF must fit an upload limit such as 100KB, 200KB, 500KB or 1MB. Use Light Compression when quality is more important than the smallest possible file size.

The custom settings are useful when you want to control render scale, JPEG quality and image format. Lower render scale and JPEG quality usually reduce file size, while higher values preserve more clarity.

Compress PDF for email

Reduce large PDF attachments before sending them through email or messaging apps. This is useful for scanned documents, reports, certificates, invoices and form submissions.

Reduce PDF size for uploads

Many job, college, government, bank and business portals have PDF upload size limits. Use light, balanced, strong or grayscale compression to make your PDF easier to upload.

Browser-based PDF compression

SmartTools processes the PDF in your browser, so compression starts quickly and avoids the waiting time usually seen on upload-heavy PDF websites.

Compress PDF to smaller sizes

If you need to compress a PDF to 100KB, 200KB, 500KB or under 1MB, start with balanced compression and then try strong compression if the file is still too large. For scanned documents, enabling grayscale can reduce the PDF size even more.

The final compressed PDF size depends on the original file. PDFs with large photos, scanned pages and presentation images usually shrink more. Text-only PDFs, digitally generated invoices or vector-heavy files may already be optimized and may not reduce much.

Best use cases

Compress PDF for email attachments.
Reduce PDF size for online application forms.
Make scanned documents smaller before uploading.
Compress reports, invoices, notes and certificates.
Reduce PDF size for WhatsApp, cloud storage and sharing.
Prepare PDF files for job, exam, bank or government portals.

PDF compression tips

Use balanced mode first for everyday PDF compression.
Use strong mode when file size is more important than clarity.
Use grayscale for black-and-white scans or documents.
Use custom settings if you want more control over quality.
Check the output PDF before submitting important documents.
Rename the output file clearly before downloading.

Important note

This PDF compressor works best for scanned and image-heavy PDFs. Strong compression may reduce image clarity because PDF pages are re-rendered into smaller images.

Your original file remains unchanged. Always review the compressed PDF before sharing it, uploading it to official portals or using it for important submissions. Password-protected, corrupted or very complex PDFs may not process correctly.

PDF Compressor FAQ

Is this PDF compressor free to use?

Yes. SmartTools PDF Compressor is free to use online for reducing PDF file size from your browser.

Does SmartTools upload my PDF to a server?

The PDF compressor is designed for browser-based processing, so compression can happen directly in your browser and avoids unnecessary upload delay.

Can I compress PDF files for email attachments?

Yes. You can reduce large PDF files before attaching them to email, uploading them to portals, or sharing them through messaging apps.

Which PDFs compress best?

Scanned PDFs, image-heavy PDFs, presentation exports and reports with large images usually compress best. Text-only or already optimized PDFs may not reduce much.

Will compression reduce PDF quality?

Light compression keeps more detail, balanced mode gives a good size-quality tradeoff, and strong compression can reduce visual clarity to create a smaller file.

Can I compress a PDF to 100KB or 200KB?

You can try strong compression and grayscale mode to reduce PDF size. The final size depends on the original PDF content, page count, image quality and scan resolution.

Can I rename the compressed PDF output?

Yes. You can edit the output file name before downloading the compressed PDF.

Will my original PDF file change?

No. The original file remains unchanged. The tool creates a new compressed PDF file for download.

Why did my PDF become larger after compression?

Some PDFs are already optimized or contain mostly text/vector content. Re-rendering such PDFs may sometimes produce a similar or larger file.

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