Optimizing Web Images: Quick Wins with MiniJPG

November 25, 2025

Small changes to how you prepare and compress images can yield big bandwidth and performance wins. Here are practical, easy-to-apply tips for getting better results with MiniJPG’s client-side compressor.

1. Resize before you compress

Delivering enormous images to the browser and relying on compression alone wastes bytes. Resize images to the maximum display size they’ll appear at — usually 2x the CSS pixel size for high-density screens is enough — then compress.

• Resize with the appropriate interpolation (bicubic or lanczos) for photographs.
• For thumbnails and avatars, downscale aggressively; the human eye tolerates more loss at small sizes.

2. Choose the right quality setting

Quality is a balance between filesize and visible artifacts. Start around 75 for photos and 60–70 for social thumbnails. Use visual checks rather than a single metric.

• For product photos keep quality higher (80+).
• For decorative images try 60–70 and compare.

3. Use progressive JPEGs when appropriate

Progressive JPEGs (scan-optimized) give the perception of faster loads because a low-quality preview appears quickly and refines. This is great for slower networks or large hero images.

• Progressive is especially useful for large images on mobile.
• Some tools may add a small overhead — test for your use-case.

4. Strip unnecessary metadata

Remove EXIF metadata and color profiles you don’t need. Metadata can add several kilobytes that provide no benefit to most web use-cases.

• Keep metadata only when needed (e.g., copyright info you must preserve).

5. Batch process with consistent settings

When compressing many images, create a small set of presets (e.g., hero, inline, thumbnail) and apply them consistently. This ensures predictable quality and consistent assets across your site.

6. Automate checks with a quick visual diff

Add a lightweight visual QA step: after compression, glance or run a pixel-diff for critical images (homepage hero, product shots). This guards against unexpected artifacting.

7. Favor perceptual tuning over raw metrics

Metrics like SSIM or MS-SSIM help, but visual perception is king. If an image looks fine at 60 quality and saves 30% bytes, that’s usually the better tradeoff than preserving high PSNR.

Conclusion

Combining sensible resizing, conservative quality settings, progressive scans where helpful, and stripping metadata will give you the best balance of visual fidelity and file size. MiniJPG’s local, WebAssembly-powered compressor makes these workflows fast and private — try building a small preset library and batch-process your image pipeline for the greatest wins.

If you’d like, I can add an example image preset configuration to the repo or create a short demo page that shows before/after comparisons using the new post as the guide.