Compress and resize your images instantly. Your images never leave your browser. All processing happens locally.
Drag & drop images here or
Supports PNG, JPG, JPEG, WebP (max 10 images)
Image compression is the process of reducing the file size of an image while preserving as much visual quality as possible. There are two main types of compression: lossy and lossless. Lossy compression permanently removes some image data to achieve smaller file sizes, which is ideal for photographs and web graphics where a slight reduction in quality is imperceptible to the human eye. Lossless compression, on the other hand, reduces file size without discarding any data, making it suitable for images that require pixel-perfect accuracy such as logos, icons, and technical diagrams. This tool uses the Canvas API built into modern browsers to re-encode your images at the quality level you choose, giving you full control over the tradeoff between file size and visual fidelity.
Using the DOLY Studio Image Compressor is simple and straightforward. Start by dragging and dropping your images onto the upload area, or click to browse your file system. You can upload up to ten images at a time in PNG, JPG, or WebP format. Once your images are loaded, adjust the quality slider to set your desired compression level — lower values produce smaller files, while higher values preserve more detail. If you need to resize your images, enter a target width or height in pixels and enable the aspect ratio lock to prevent distortion. You can also choose an output format different from the original, for example converting a PNG to WebP for significantly smaller file sizes. Click the Compress All button to process every image in the batch. The tool displays a side-by-side preview of the original and compressed versions along with detailed file size savings. Download individual images or grab all of them at once in a convenient ZIP archive.
To get the best results from image compression, consider the following strategies. For photographs, JPEG or WebP at 70 to 85 percent quality typically delivers an excellent balance between size and appearance. For images with transparency, PNG is required, though WebP also supports alpha channels with better compression ratios. Resizing images to match their display dimensions on your website eliminates unnecessary pixels that only add to the file size without improving the viewer's experience. A hero image displayed at 1200 pixels wide does not need to be uploaded at 4000 pixels. When compressing for the web, aim for images under 200 kilobytes whenever possible, as large images are one of the primary causes of slow page load times and poor Core Web Vitals scores. Always check the before-and-after preview to ensure the compressed version meets your visual standards before downloading.
No. All image processing happens entirely within your browser using the HTML5 Canvas API. Your images are never uploaded to any server. This means your photos, screenshots, and documents remain completely private and secure on your own device. You can even disconnect from the internet after loading the page and the tool will continue to work.
The compressor supports PNG, JPG (JPEG), and WebP formats for both input and output. You can convert between formats freely — for example, upload a PNG and download it as a WebP file for significantly smaller file sizes. The tool automatically detects the original format and uses it as the default output unless you choose a different one.
The amount of compression depends on the original image, the chosen quality level, and the output format. In general, you can expect reductions of 30 to 80 percent for JPEG and WebP images at quality settings between 60 and 80 percent. Converting from PNG to WebP often yields even larger savings. The tool shows the exact before and after file sizes along with the percentage saved, so you can fine-tune the settings to your needs.
Because processing runs in your browser, the practical limits depend on your device's memory and processing power. Most modern devices handle images up to 20 megapixels without any issues. You can upload up to 10 images per batch. For very large or high-resolution images, processing may take a few extra seconds.