Image Compressor

Image compression reduces file size by removing unnecessary data while preserving visual quality. This tool uses the HTML5 Canvas API to decode your image, then re-encodes it with adjustable quality settings. For JPEG images, the compression algorithm discards high-frequency color data that human eyes struggle to perceive, achieving significant file size reductions.



The compression happens entirely in your browser—no images are uploaded to servers. When you select an image, JavaScript reads the file, draws it onto a canvas element, and uses the canvas.toBlob() method to generate a compressed version. The quality slider (0-100) controls the compression level: higher values preserve more detail but result in larger files, while lower values create smaller files with potential quality loss.



Different image formats compress differently. JPEG works best for photographs with complex colors and gradients. PNG is ideal for graphics with sharp edges and transparency, though it compresses less efficiently. WebP offers superior compression for both photos and graphics, though browser support is universal only in modern browsers.

1. Website Performance Optimization
Large images are the primary cause of slow-loading websites. Compressing hero images, product photos, and blog post illustrations can reduce page load times by 50-70%. A 2MB hero image compressed to 200KB loads 10x faster, directly improving user experience and SEO rankings. Google's Core Web Vitals heavily penalize slow-loading images.



2. Email Attachments
Many email providers limit attachment sizes to 10-25MB per message. Compressing photos before attaching them ensures delivery and faster uploads. A batch of 10 vacation photos totaling 40MB can compress to under 5MB without noticeable quality loss, making sharing via email practical.



3. Social Media Uploads
Platforms like Instagram, Facebook, and Twitter compress uploaded images automatically, often degrading quality unpredictably. Pre-compressing images with optimal settings gives you control over the final result and speeds up upload times, especially on mobile connections.



4. Mobile App Development
App bundle size directly impacts download rates. Compressing app assets (icons, splash screens, UI elements) reduces the overall app size. Studies show that every 6MB reduction in app size increases download conversion by 1%. For apps with hundreds of images, compression is essential.



5. Bandwidth Cost Reduction
For high-traffic websites, image bandwidth can cost hundreds of dollars monthly. A site serving 1 million page views with 2MB of images per page transfers 2TB of data. Compressing images to 400KB reduces bandwidth to 400GB—saving significant hosting costs.

• Start with 80-85% quality: This sweet spot provides excellent visual quality while reducing file size by 50-70%. Most viewers cannot distinguish between 100% and 85% quality.



• Use JPEG for photos, PNG for graphics: Photographs compress well as JPEG. Logos, screenshots, and graphics with text should use PNG to preserve sharp edges. Never use JPEG for images with transparency.



• Resize before compressing: If displaying an image at 800px width, don't upload a 4000px version. Resize first using our Image Resizer, then compress. A 4000px image compressed to match an 800px file size will still be larger and slower.



• Compare before/after: Always preview the compressed image before downloading. Zoom to 100% and check critical details. If you notice artifacts (blocky areas or color banding), increase the quality setting slightly.



• Batch processing saves time: If compressing multiple images for a project, use consistent settings. This ensures uniform quality across your website or presentation.



• Consider WebP for modern sites: WebP provides 25-35% better compression than JPEG with the same visual quality. If your audience uses modern browsers (95%+ support in 2026), WebP is the superior choice.



• Keep original files: Always save uncompressed originals. Compression is lossy for JPEG—repeatedly compressing the same file degrades quality further. Work from originals when creating different sizes or versions.