ImageOptim for Designers: Lossless Image Compression Tool

ImageOptim is a Mac app that compresses PNG, JPEG, and GIF images using lossless optimization techniques. It removes invisible junk like EXIF metadata, embedded thumbnails, and color profiles while re-encoding images with better compression algorithms. The result is 10-50% smaller files that look pixel-identical to the originals. Web designers use it to speed up page loads without quality trade-offs.

Key Specs

How Designers Use ImageOptim

ImageOptim fits into the final optimization step before deploying images.

For Web Performance Optimization

After exporting images from Figma, Photoshop, or design tools, drag them into ImageOptim before uploading to your site. It strips camera metadata from JPEGs, removes unused color profiles from PNGs, and re-encodes GIFs with better compression. This reduces page weight by 20-40% without changing how images look. Faster load times improve SEO, user experience, and conversion rates.

For App Asset Optimization

Mobile and desktop apps ship with image assets that affect download size and startup time. Run all icons, backgrounds, and UI graphics through ImageOptim before adding them to Xcode or Android Studio. The lossless compression shrinks app bundles by megabytes without requiring lossy formats that reduce quality. This is especially important for apps targeting users on slow connections or limited data plans.

For Batch Processing Design Exports

Export hundreds of product images, blog post graphics, or email assets from your CMS or design tool, then drag the entire folder into ImageOptim. It processes batches automatically, preserving folder structure. For recurring workflows, use ImageOptim’s command-line interface in shell scripts or integrate it into automated pipelines that optimize every image on save.

ImageOptim vs. Alternatives

How does ImageOptim compare to other image compression tools?

Choose ImageOptim if: You’re on Mac, need lossless compression, want to process batches offline, and prefer owning your optimization tools.

Choose ImageAlpha if: You need aggressive PNG compression and can accept lossy quality trade-offs (use before ImageOptim for best results).

Choose TinyPNG if: You need quick web-based lossy compression without installing software, or you’re on Windows/Linux.

Choose Squoosh if: You want to experiment with modern formats (WebP, AVIF) in a browser with visual quality comparisons.

Getting Started with ImageOptim

A 5-minute workflow to compress images:

Step 1: Download and install

Visit imageoptim.com/mac (not the App Store) and download the free app. Drag it to Applications. Launch it. There’s no setup or configuration needed. The default settings work for most use cases.

Step 2: Drag images or folders

Drag PNG, JPEG, or GIF files into the ImageOptim window. You can also drag entire folders, and it processes all images recursively. The app shows a progress bar and file size savings for each image. Compressed files replace the originals (make backups if you’re cautious).

Step 3: Check the results

ImageOptim displays how much space it saved (percentage and bytes). Images that couldn’t be compressed further show 0% savings. The optimized images are pixel-identical to the originals. Upload them to your website, app, or design system and measure the performance improvement.

ImageOptim in Your Design Workflow

ImageOptim sits at the end of the export process, right before deployment.

• Before ImageOptim: Design in Figma/Sketch, export images at high quality, use ImageAlpha for lossy PNG compression (optional)
• During ImageOptim: Drag exported images into app, let it strip metadata and re-encode losslessly
• After ImageOptim: Upload optimized images to web server, CDN, or app bundle, measure page load improvements

Common tool pairings:

• ImageOptim + ImageAlpha for double compression (lossy PNG reduction first, then lossless optimization)
• ImageOptim + JPEGmini for JPEG workflows (lossy JPEGmini first, then lossless ImageOptim cleanup)
• ImageOptim + Figma for exporting designs and immediately optimizing before deployment
• ImageOptim CLI + Webpack for automated image optimization in build pipelines
• ImageOptim + Cloudflare Polish for combining local optimization with CDN-level compression

Common Problems (and How to Fix Them)

These issues come up when using ImageOptim for compression.

“ImageOptim didn’t reduce my file size”

Your image is already optimized. Export tools like Figma and modern cameras sometimes output well-compressed images. ImageOptim can’t improve files that are already using optimal compression. Try ImageAlpha (for PNGs) or JPEGmini (for JPEGs) for lossy compression that achieves bigger savings.

“I need ImageOptim on Windows or Linux”

ImageOptim is Mac-only. On Windows, use FileOptimizer or Radical Image Optimization Tool (RIOT). On Linux, use Trimage or install the underlying tools (pngquant, MozJPEG, Gifsicle) via package managers. For cross-platform workflows, use web-based tools like Squoosh or TinyPNG’s API.

“Can I automate ImageOptim in my build process?”

Yes. Install ImageOptim’s CLI via Homebrew (brew install imageoptim), then call it in shell scripts: imageoptim --quit *.png. Integrate it into npm scripts, Gulp tasks, or CI/CD pipelines. The CLI version runs headless and exits after processing, perfect for automated workflows.

“ImageOptim replaced my original files and I needed them”

ImageOptim overwrites files by default to save disk space. If you need to keep originals, duplicate the folder before processing or use the CLI with output directory flags. For production workflows, always version control your source files in Git so you can recover originals if needed.

“Some of my images look worse after ImageOptim”

ImageOptim uses lossless compression. If images look different, check your viewing environment (color management, display calibration). The pixel data is identical. If you see visible changes, you might have used ImageAlpha or another lossy tool before ImageOptim. ImageOptim itself never degrades quality.

“I accidentally downloaded a fake ImageOptim from the App Store”

The real ImageOptim is not on the App Store. The developer warns users to beware of knock-offs. Download only from imageoptim.com/mac. Delete any App Store version and get the official free download. The real app is open-source and doesn’t charge for features.