Free Online Image Compressor — Reduce Image File Size Instantly
ExperToolBox's image compressor reduces the file size of your JPG, PNG and WebP images directly in your browser, without uploading them to any server. Use the quality slider to find the perfect balance between file size and visual quality, then download your compressed image instantly.
Image compression is one of the most impactful optimisations you can make for website performance. Studies show that images account for over 50% of the average webpage's total weight. By compressing your images, you reduce load times, improve your Google PageSpeed score and provide a better experience for your users.
Why compress images?
Large images are the most common reason websites load slowly. A typical uncompressed photo from a modern smartphone can be 4–8MB. The same image compressed to 80% quality is typically 300–600KB — a reduction of over 90% with virtually no visible difference to the human eye.
Faster websites rank higher in Google search results, have lower bounce rates, and convert better. For e-commerce sites, even a one-second improvement in load time can increase conversions by 7%. Image compression is one of the quickest and highest-impact optimisations available.
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100% private
Images processed locally, never uploaded
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Quality slider
Control the compression level precisely
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Live preview
Compare original vs compressed side by side
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Size savings
See exactly how much space you saved
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Instant
Results appear as you move the slider
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Free forever
No limits, no watermarks, no signup
Frequently Asked Questions
What quality setting should I use?
For most web use, 75–85% quality provides an excellent balance between file size and visual quality. Below 60%, compression artefacts become visible. For images that will be printed, use 90%+ quality.
Does this tool compress PNG files?
Yes, but with an important note: PNG uses lossless compression, so to achieve significant size reduction, the output is converted to JPEG format. If you need transparency (alpha channel), use a dedicated PNG optimizer.
Is there a file size limit?
No. The tool processes images in your browser using the HTML5 Canvas API. The only limit is your device's available memory. Very large images (above 6000×6000px) may take a moment to process.
Will my images be stored on your servers?
No. All processing happens locally in your browser. Your images are never sent to our servers, never stored, and never seen by anyone other than you.
What is the difference between lossy and lossless compression?
Lossy compression (used here for JPEG) permanently removes some image data to achieve smaller file sizes. Lossless compression (PNG, GIF) reduces file size without losing any data. For photographs, lossy compression at high quality settings is usually indistinguishable from the original.
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