Image Optimizer
Compress and optimize images directly in your browser. Adjust quality, resize, and convert formats — all client-side.
Frequently Asked Questions
How much can I reduce image file size?
Typical reductions: 40–80% for JPEG/PNG with minimal quality loss. Converting PNG to WebP can save 25–35% additional size.
Is image quality affected?
You control the quality slider. 80–90% quality is visually lossless for most web images while significantly reducing file size.
Are my images uploaded to a server?
No. All optimization runs in your browser using Canvas API. Your images never leave your device.
What image formats are supported?
Input: JPEG, PNG, WebP, GIF. Output: JPEG, PNG, WebP. WebP typically offers the best compression ratio.
Can I resize images while optimizing?
Yes, enter a target width and the image will be proportionally resized during optimization.
Why Image Optimization Matters
Images are the single largest contributor to page weight on most websites. According to the HTTP Archive, images account for over 50% of the average page's total transfer size. Unoptimized images directly hurt load times, bandwidth costs, and — critically — Google's Core Web Vitals metrics, especially Largest Contentful Paint (LCP).
Compressing images before uploading to a CMS, CDN, or web app is the highest-ROI optimization available: a 500 KB hero image converted to WebP at 85% quality typically shrinks to under 80 KB with no perceptible visual difference.
Image Format Comparison
| Format | Compression | Transparency | Best for |
|---|---|---|---|
| JPEG | Lossy | No | Photos, complex images with many colors |
| PNG | Lossless | Yes | Screenshots, logos, images with text or sharp edges |
| WebP | Both | Yes | Everything — best ratio for web delivery |
| AVIF | Both | Yes | Cutting-edge; best compression but limited tooling |
| GIF | Lossless | Yes | Simple animations only (consider WebP animation instead) |
| SVG | Vector | Yes | Icons, logos, illustrations — infinitely scalable |
Image Optimization & Core Web Vitals
- Largest Contentful Paint (LCP) — the hero image is usually the LCP element. Google targets <2.5 s. Compress it, serve WebP, and use a CDN.
- Cumulative Layout Shift (CLS) — always set explicit
widthandheightattributes so the browser reserves space before the image loads. - Interaction to Next Paint (INP) — large images decoded on the main thread cause jank. Use
loading="lazy"for below-fold images. - Use responsive images — serve different sizes via
srcsetso mobile users don't download a 2000 px wide image.