Bulk Image Compressor

100% Private — Files never leave your device

Drop dozens of images at once and get a single ZIP back. Each image is compressed independently using your chosen quality setting.

Drop images here

JPG, PNG, WEBP · max 10 MB each · up to 30 files · 100 MB total

How bulk compression works

  1. Drop or paste multiple images into the upload box.
  2. Pick a quality level — 75 is a great default.
  3. Optionally convert all outputs to JPG or WEBP for consistency.
  4. Click Compress & download ZIP. Each image is compressed using your browser's Canvas API and packaged into a single ZIP for one-click download.

When to use bulk compression

Compressing dozens of photos individually is tedious. This tool runs the same Canvas-based compression as our single-image Image Compressor across every file you drop in, then packages the results into a ZIP — using JSZip, an open-source library that runs entirely in your browser. Useful for: preparing a wedding photo album for sharing, optimising blog post images before upload, shrinking a phone-camera roll for cloud backup, or batching website assets before deployment.

Need a target file size instead of a quality slider? Use the Image Resizer. Need to change formats only? Try the Image Format Converter.

How bulk compression saves time

Drop in up to 30 images at once (max 100 MB total) and the tool compresses each one in parallel using the quality setting you choose. The result downloads as a single ZIP file containing all the compressed versions. For a typical batch of 25 phone photos averaging 4 MB each (100 MB total), expect compressed output around 12-25 MB depending on quality setting.

When bulk compression matters

File size limits explained

The tool processes up to 30 files at once and 100 MB total — these limits keep the browser tab responsive. For larger batches, run multiple rounds. The processing happens entirely in your browser using a Web Worker, so the rest of your browser stays usable while a 100 MB batch compresses (typically 30-90 seconds depending on your laptop). The compressed ZIP downloads automatically when complete.

Privacy note

Even with 30 files at once, nothing leaves your device. Each image is read from your file system, compressed in-memory, and added to the ZIP — all in JavaScript inside the browser tab. The ZIP itself is generated client-side using JSZip, then offered as a download via a Blob URL. There is no server-side step.

Disclaimer

Higher-quality settings produce larger files. The "high" quality (90%) is appropriate for archival sharing; "medium" (75%) for normal web use; "low" (50%) for thumbnails or previews where size trumps quality. Always preview a sample before committing to a batch — re-compressing already-compressed images compounds quality loss.

FAQ

How much will I save?

For most phone photos at quality 75, expect 60–80% size reduction. Already-small images may not shrink further.

Are my files uploaded?

No. Compression and ZIP packaging both happen in your browser. Nothing is sent anywhere.

What's the maximum batch size?

30 files in this version, each up to 10 MB. The real limit is your device's memory — phones may struggle past 10–15 large images.