Image Compressor
Reduce image file size without sacrificing quality. Runs entirely in your browser — your files never leave your device.
Drop your image here
or click to browse your files
Compressing…
How It Works
Everything runs inside your browser using the HTML5 Canvas API — no server, no network, fully private.
Upload Your Image
Drag and drop or click to browse. Supports JPG, PNG, WebP, GIF, BMP, TIFF, AVIF, and HEIC.
Set Quality & Format
Adjust the quality slider from 1% (smallest file) to 100% (best quality). Choose your output format.
Compress
Click Compress. The Canvas API re-encodes your image at the chosen quality instantly in your browser.
Download
Review the before/after sizes and comparison views, then download your compressed image.
What This Tool Does
Fully Private
Images are never uploaded to any server. All processing runs locally in your browser. Nothing is retained when you close the tab.
Adjustable Quality
A 1–100% quality slider gives you precise control over the tradeoff between file size and visual quality.
4 Preview Modes
View original only, compressed only, side-by-side comparison, or an interactive drag-slider comparison.
Live Size Stats
See exactly how many KB you saved and what percentage reduction was achieved after each compression run.
Multi-Format Support
Accepts JPG, PNG, WebP, GIF, BMP, TIFF, AVIF, and HEIC where browser support allows. Outputs JPEG, WebP, or PNG.
Aspect Ratio Preserved
Images above 4096px are auto-scaled proportionally before encoding — preventing memory issues without distortion.
Why Compress Images?
Large image files are one of the most common causes of slow-loading web pages. A photograph taken on a modern smartphone can easily be 4–8 MB in its original form. Uploading that directly to a website means every visitor has to download that data — which pushes up page load times, increases bandwidth costs, and can hurt your search engine rankings.
Compressing images before you use them online is one of the simplest performance improvements you can make. Even reducing a 3 MB image to 300 KB — a 90% reduction — is often imperceptible to the human eye at normal viewing sizes, especially when viewed on a screen rather than printed at large scale.
JPEG vs WebP vs PNG — Which Should You Use?
The output format matters as much as the quality setting. Here's a practical guide:
- JPEG — Best for photographs and images with colour gradients. Supports lossy compression so files can be made very small. No transparency support.
- WebP — A modern format that achieves smaller files than JPEG at equivalent visual quality. Supports lossy, lossless, and transparency. The best default choice for web use in most cases.
- PNG — Best for images requiring a transparent background, or logos and graphics with flat colours where JPEG artefacts would be noticeable. Uses lossless compression.
Understanding the Quality Setting
The quality slider controls how aggressively the encoder compresses your image. At 100% the output is as close to lossless as the format allows. At lower settings the encoder discards progressively more data, creating smaller files at the cost of introducing visible artefacts.
For most web photography, quality settings between 70% and 85% strike a good balance — significant file size reduction with compression that is very difficult to spot unless images are viewed side by side or at very large sizes.
A Note on Transparency
If your image has a transparent background — common with logos, icons, and PNG files — output to PNG or WebP rather than JPEG. JPEG does not support transparency and will fill transparent areas with solid white. WebP preserves transparency while still achieving good compression.
Large Images and Memory
This tool automatically limits image dimensions to a maximum of 4096 × 4096 pixels before encoding. Images larger than this are scaled down proportionally. This prevents the browser from running out of memory when processing high-resolution photographs and ensures practical output file sizes for web use.
Frequently Asked Questions
No. Everything happens in your browser using the HTML5 Canvas API. Your image is read from your device, processed in memory, and the result is made available for download — all without any network request. Your images are never uploaded anywhere.
You can upload JPG, PNG, WebP, GIF (first frame), BMP, and TIFF files. AVIF and HEIC support depends on your browser. You can download the result as JPEG, WebP, or PNG regardless of the input format.
Only if your image is very large. Images wider or taller than 4096 pixels are scaled down proportionally to prevent browser memory issues. Below that threshold, the output dimensions match the original exactly. Aspect ratio is always maintained.
For web photography, 70–85% is a good starting point — it typically reduces file sizes by 50–80% with compression that is difficult to spot at normal viewing sizes. For thumbnails you can go lower. For quality-critical images, stay above 85%.
PNG uses lossless compression — the quality slider has no effect on PNG output because there is no "quality" concept in the PNG spec. If file size matters more than transparency, switch to JPEG or WebP, which support lossy compression and produce much smaller files.
Only the first frame of a GIF is processed. The Canvas API does not support re-encoding multi-frame GIF animations. If you upload an animated GIF, the result will be a static image of the first frame.