How to Compress Images for Your Website (Without Visible Quality Loss)
The right sizes, formats and quality settings to make website images load fast — and how to compress them in bulk for free.
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Images are usually the heaviest part of a web page. A single 5 MB phone photo used as a banner can take seconds to load on mobile data, hurting Core Web Vitals, rankings and conversions. Compressing correctly typically cuts 80–95% of the weight with no visible difference.
Three steps that matter
1. Resize to the displayed size
A photo displayed 1200 px wide doesn't need to be 4000 px wide. As a rule, export at the largest size it will be shown (2× for sharp Retina display of small images).
| Use | Suggested width |
|---|---|
| Full-width hero | 1920 px |
| Blog / content image | 1200 px |
| Product image | 1000–1500 px |
| Card thumbnail | 400–600 px |
2. Choose a modern format
WebP is 25–35% smaller than JPG at the same quality and supported by every modern browser. Keep PNG for logos and screenshots.
3. Pick the right quality
75–82% is the sweet spot for photos. Below ~60% you start to see artefacts; above ~90% the file grows quickly for no visible gain.
Compress images in bulk
- Open the free Image Compressor.
- Add all your images.
- Set quality (start at 75%), choose WebP or keep the original format, and set a maximum width (e.g. 1920 px).
- Compare before/after sizes and download as a ZIP.
Targets worth aiming for
- Hero images under ~200 KB
- Content images under ~100 KB
- Thumbnails under ~30 KB
- Total page weight under ~1.5 MB on mobile
Beyond compression
- Lazy-load images below the fold (
loading="lazy"). - Set width and height attributes to prevent layout shift.
- Use responsive images (
srcset) so phones download smaller versions. - Don't use images for text — real text is sharper, smaller and indexable.
Your images stay on your device
Pyalm's image tools process files with your browser's canvas. Nothing is uploaded — useful for ID photos, product shots before launch, and screenshots containing customer data.
Fast websites, without the manual work
Unoptimised images are the most common reason business websites load slowly — and slow pages lose both rankings and enquiries. Pyalm builds fast, SEO-ready websites in Next.js where every uploaded image is resized, converted to modern formats and lazy-loaded automatically.
Related free tools
Image Converter | Image Compressor | Image Resizer | Image Cropper | All free tools