Image Compressor
Compress JPEG, PNG, and WebP images directly in your browser. No files are ever uploaded — your privacy is guaranteed.
Drag & drop an image here
or click to browse
Supports JPEG, PNG, WebP — max 20MB
Compress Images Without Compromising Privacy
Our Image Compressor is designed with privacy as the number one priority. Unlike most online image compression tools that require you to upload files to remote servers, every operation here happens entirely in your browser using the HTML5 Canvas API. Your images never leave your computer — not a single byte is transmitted over the network. This means you can compress sensitive documents, personal photos, or confidential design assets with complete peace of mind.
How Browser-Based Compression Works
When you select an image, the browser loads it into memory and draws it onto an invisible HTML5 Canvas element. The Canvas API's toBlob() method lets us re-encode the image at your chosen quality level — all locally on your device. This approach is not only privacy-friendly but also incredibly fast, since it avoids network latency entirely. The entire process takes milliseconds for most images.
Understanding Image Quality vs. File Size
Image compression is a balancing act between visual quality and file size. The quality slider lets you control this tradeoff: a setting of 100 preserves near-original quality but produces larger files, while lower values like 50–70 dramatically reduce file size with a manageable loss in visual fidelity. For web use, quality settings between 70–85 typically offer the sweet spot — files are lightweight enough for fast page loads while remaining crisp to the human eye.
JPEG vs. PNG vs. WebP: Choosing the Right Format
- JPEG: Best for photographs and images with smooth color gradients. Lossy compression — some detail is permanently discarded to reduce file size. Cannot preserve transparency.
- PNG: Lossless compression — no quality degradation. Ideal for logos, screenshots, icons, and any image requiring sharp edges or transparency. Files tend to be larger than JPEG.
- WebP: A modern format from Google that supports both lossy and lossless compression, plus transparency. WebP files are typically 25–34% smaller than comparable JPEGs at equivalent quality. Widely supported in all modern browsers.
When Should You Compress Images?
Image compression is essential for web performance. Uncompressed images are often the single largest contributor to slow page load times, directly impacting user experience and SEO rankings. Compressing images before uploading them to your website, CMS, or social media can reduce bandwidth consumption by 50–80% without a visible difference. It's also crucial for email attachments (many providers cap attachment sizes at 25MB) and for reducing storage costs in cloud services.
Why Choose Our Compressor Over Others?
Most "free" image compression tools require you to upload files to their servers, where they may be stored, analyzed, or even resold. Some impose daily limits or watermarks until you pay. Our tool has zero limitations — compress as many images as you want, at any resolution, with no sign-up, no ads that track you, and no hidden data collection. Everything runs on your hardware. We don't even use analytics scripts that could leak your data. It's compression the way it should be: fast, free, and fully private.
💡 Pro Tips for Maximum Compression
- Resize before compressing: If your original image is 4000×3000px but you only need 1200px wide for the web, resize it first. Reducing dimensions + compressing can shrink a 5MB photo to under 100KB.
- Use WebP as output: Switch the format dropdown to WebP for the best compression ratio — typically 25-35% smaller than JPEG at the same visual quality. All modern browsers support it.
- Batch process for consistency: Compressing multiple images? Stick to the same quality setting (e.g., 75%) and format for a uniform look across your entire site.
Frequently Asked Questions
Does compression reduce image dimensions?
No — our compressor preserves the original pixel dimensions (width × height). It only reduces file size by re-encoding at a lower quality setting. If you need to resize, use a separate tool first.
Is there a file size limit?
Yes, 20MB per file. This covers virtually all photos from modern smartphones and DSLRs. For larger files (e.g., RAW camera output), convert to JPEG/PNG first.
Can I convert PNG to WebP or JPEG with this tool?
Absolutely! The format dropdown lets you choose any output format regardless of input. For example, compress a PNG screenshot into a much smaller WebP file for your documentation site.
Why did my PNG become larger after compression?
PNG uses lossless compression — it cannot discard detail like JPEG. If you set a high quality value on a PNG, the output may actually be slightly larger. For maximum PNG savings, consider converting to WebP instead.
What quality setting should I use for web images?
70-80% is the sweet spot for most web images — visually near-identical to the original on screen but 60-80% smaller. Use 85% for hero images and photography portfolios, and 60% for thumbnails or icons where detail matters less. The side-by-side preview lets you compare original vs. compressed before downloading, so you can dial in the right balance for your use case.
Can I use this for GitHub README screenshots?
Yes — it's perfect for README images. GitHub repos with large screenshots slow down page loads and eat into your LFS bandwidth. Drop your screenshot into the compressor, set quality to 70% and format to WebP, and you'll typically get a 80-90% size reduction with no visible quality loss at README display sizes.
Does this work offline or on slow connections?
Yes! Once the page is loaded, the compressor works entirely offline — no internet required. All image processing runs locally via the Canvas API, so it works on planes, in remote areas, or on metered connections. The tool page itself is ~20KB, so it loads instantly even on 2G/3G.