How to Compress Multiple Images at Once with Bulk Image Compressor

Updated

Bulk Image Compressor (imagecompressr.com) compresses batches of JPG, JPEG, PNG, and WebP files directly in your browser — no upload, no signup, and no stated limit on how many images you can drop in at once. You drag your files into the dropbox, optionally set a target size or maximum dimensions, and click Start Compressing. The catch: the first 100 images are free, and unlimited compression requires a one-time $10 purchase.

Before you start

  • File types supported: JPG, JPEG, PNG, WebP.
  • Where your files go: the page states images "stay on your machine" and are not uploaded to a server, so compression runs locally in the browser.
  • Free limit: your first 100 images are free; beyond that the site asks for a one-time payment (no subscription).
  • No account needed to begin — signup is not required to compress.

Step-by-step: batch compress images

  1. Add your images. Drag and drop as many files as you want into the dropbox, or click Select files to browse. The counter shows how many images are selected (e.g., "Selected 0 images").
  2. Choose your settings.
    • Leave the defaults to compress immediately, or
    • Open Advance Settings to control output.
  3. Set quality (optional). Use the Quality slider (shown as a percentage). The algorithm is not lossless, but the site notes that selecting 95%+ quality gives near-lossless results.
  4. Set a target size (optional). Enter a Max Size in KBs to bring large files down from MBs to KBs.
  5. Set maximum dimensions (optional). Enter a max target width and height in pixels — for example, 512 — to make every image fit within that range (e.g., all images smaller than 512×512).
  6. Click Start Compressing. The tool processes the whole batch and returns your compressed images to download.

Matching the setting to your goal

Your goal What to set
Smallest file size, quality less critical Lower the Quality percentage
Near-lossless result Quality at 95% or higher
Hit a specific file size (e.g., for upload limits) Set Max Size in KBs
Uniform dimensions (e.g., thumbnails) Set max width/height, such as 512×512
Just shrink everything quickly Leave defaults and compress

Common sticking points

  • "Lossless" isn't truly lossless. The site is explicit that the algorithm is not lossless; use 95%+ quality if you need results that look unchanged.
  • Target size vs. dimensions are different controls. Max Size (KBs) limits file weight; max width/height limits pixel dimensions. Set both if you need files that are small and a specific shape.
  • The 100-image free limit. If you're compressing a large library, expect to hit the paywall; the $10 one-time purchase unlocks unlimited compression.
  • Photos vs. graphics. The site positions itself as a photo compressor and claims drastic size reductions on photos, so it's aimed at image-heavy batches rather than precision editing.

When this tool fits

Use Bulk Image Compressor if you need to shrink many JPG/PNG/WebP files at once without uploading them anywhere, and you want control over either output file size or pixel dimensions. If you only have a handful of images, the free 100-image allowance covers you. If you're processing thousands regularly, the one-time $10 unlock removes the cap.