How to Reduce File Size — Images, PDFs, Videos & Documents 2026

File size matters for email attachments, uploads, storage limits, and sharing. The right approach depends on the file type — images, PDFs, videos, and documents each have different compression strategies. This guide covers all of them.

Reduce Image File Size

Images are the most common cause of oversized documents and slow websites. The key is choosing the right format and compression level.

Option A — Squoosh (Free, Browser-Based, Best Quality)

1. Open squoosh.app
2. Drag your image onto the page
3. In the right panel, change the codec to WebP or MozJPEG
4. Drag the quality slider — 75-85% is typically imperceptible to human eyes
5. Click the download icon to save

Squoosh runs entirely in your browser — images stay on your device. Typical result: 60-80% size reduction at 80% quality with no visible degradation.

Option B — FileShot Compressor

fileshot.io/tools/compressor — upload images, choose output quality or format, download optimized version. Supports JPEG, PNG, WebP, GIF.

Option C — Windows Paint (Quick Resize)

1. Open the image in Paint
2. Click Resize in the toolbar
3. Enter a percentage (e.g., 50%) to halve dimensions
4. Save — smaller dimensions = smaller file

Resizing dimensions reduces file size more aggressively than quality compression. A 4000x3000px photo resized to 2000x1500px at the same quality is approximately 1/4 the file size.

Option D — Mac Preview

1. Open image in Preview
2. Tools → Adjust Size — resize dimensions
3. File → Export — choose JPEG and set Quality slider

Reduce PDF File Size

Option A — Adobe Acrobat (Desktop, Best Quality)

1. Open the PDF in Adobe Acrobat
2. File → Save as Other → Reduced Size PDF
3. Choose the compatibility version (newer = smaller) → click OK

Acrobat Reader does not include this feature — Acrobat Pro is required. A free trial is available.

Option B — FileShot PDF Tool

1. Open fileshot.io/tools/pdf
2. Upload the PDF
3. Use the compress option
4. Download the smaller version

Option C — Chrome Print to PDF (Quick Hack)

1. Open the PDF in Chrome
2. Press Ctrl+P (or Cmd+P on Mac)
3. Change destination to Save as PDF
4. Click Save

Chrome re-encodes the PDF during printing. This often reduces size by 20-50%, particularly for PDFs with embedded fonts or large images. Quality may differ slightly from the original.

Reduce Video File Size

Option A — HandBrake (Free, Best Quality Control)

HandBrake is the gold standard for video compression. Free, open-source, all platforms.

1. Download HandBrake
2. Open your video file
3. Under Video tab: set codec to H.265 (x265)
4. Set Constant Quality to RF 22-26 (higher number = smaller file, lower quality)
5. Under Audio: set to AAC, 128 kbps
6. Click Start Encode

H.265 achieves 30-50% smaller files than H.264 at the same visual quality. An RF of 23 is a good default for most videos.

Option B — FileShot Compressor (Online)

fileshot.io/tools/compressor — upload video, choose output quality, download compressed version. Suitable for moderate compression without installing software.

Reduce Word Document File Size

Large .docx files are usually caused by high-resolution embedded images, embedded fonts, or unused revision history.

Compress Embedded Images

1. Click any image in the document
2. In the Picture Format ribbon → click Compress Pictures
3. Select:
   • Check Delete cropped areas of pictures
   • Choose Email (96 ppi) for email attachment, or Web (150 ppi) for web sharing
4. Click OK and save

Remove Revision History

1. Review tab → Accept All Changes
2. Delete all comments
3. Save — tracked changes add significant file bloat

File Size Reduction Cheat Sheet

ZIP archives compress text well but don't meaningfully reduce already-compressed formats like JPEG, MP4, or PDF.

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