Compress JPG, PNG, and WebP images directly in your browser. Adjust image quality or dimensions, compare the original and compressed file sizes, and download the result. Your image is processed locally and is never uploaded to Toolisto.
Your images
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Image
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Your images are compressed locally in your browser and are never uploaded or stored.
Compress Images Online
The Toolisto Image Compressor reduces image file size without requiring software, registration, or an upload to a remote server. It is useful for website images, email attachments, online forms, product photos, blog posts, presentations, and social media.
Choose a JPG, PNG, or WebP file and the tool creates a compressed preview automatically. You can change the output format, adjust image quality, or reduce the width and height. The result panel shows the original size, compressed size, saved space, output dimensions, and file format before you download anything.
How to Use the Image Compressor
- Choose a JPG, PNG, or WebP image, or drag it into the upload area.
- Select the output format. WebP is recommended for a strong balance between compatibility, quality, and file size.
- Adjust the quality slider. Higher values preserve more detail; lower values usually create smaller files.
- Optionally change the width or height. Keep Keep aspect ratio enabled to avoid stretching the image.
- Review the compressed preview and file-size comparison.
- Select Download compressed image to save the result.
The tool updates the compressed result when settings change. Results vary according to the original format, image dimensions, visual detail, and selected output settings.
JPG, PNG, or WebP: Which Format Should You Choose?
| Format | Best for | Compression notes |
|---|---|---|
| JPG | Photographs and images without transparency | Adjustable quality and broad compatibility |
| PNG | Graphics, screenshots, logos, and transparency | Lossless, but the file may remain larger than JPG or WebP |
| WebP | Website images, photographs, and transparent graphics | Often creates a smaller file while preserving good visual quality |
Choose Keep original format when the existing format is required. Choose WebP when reducing file size is the main goal. Choose JPG for photographs that do not need transparency. When JPG is selected, transparent pixels are placed on a white background.
Reduce Image Size Without Noticeable Quality Loss
Image compression can reduce file size substantially, but no fixed reduction can be guaranteed for every image. A large photograph may become much smaller with little visible difference, while an image that has already been optimized may have less room for improvement.
For a good starting point, use WebP with quality set near 80%. Review the preview and increase the quality if fine details look too soft. If the file is still too large, reduce the image dimensions. Lowering a 4000-pixel-wide photo to the maximum width actually needed on a website often saves more space than aggressive quality reduction.
“Without noticeable quality loss” means that most viewers are unlikely to notice a difference at normal display size. It does not mean that the compressed file is mathematically identical to the original.
Why Image Dimensions Matter
Digital cameras and phones often create images much larger than websites, forms, or email messages require. A photo may be 4000 pixels wide even when it will only be displayed at 1200 pixels.
Reducing dimensions removes pixels that would not be visible at the intended display size. This can produce a major file-size reduction while allowing a relatively high quality setting. Keep the aspect-ratio option enabled so the width and height change proportionally.
The compressor does not enlarge images beyond their original dimensions. Upscaling would increase processing time and file size without restoring additional detail.
Private Browser-Based Image Compression
All image decoding, resizing, compression, previewing, and downloading take place locally in the visitor’s browser. The selected image is not uploaded to WordPress, sent to Toolisto, or stored in a database.
Local processing also avoids upload and server-processing delays. Performance depends on the image dimensions, file size, browser, and available device memory. Very large images may take longer to process on older phones or low-memory devices.
Frequently Asked Questions
The current version provides direct control over output format, quality, width, and height. Adjust these settings while watching the resulting file size. Exact results depend on the content of the image, so the same settings can produce different file sizes for different pictures.
JPG and WebP use adjustable compression. Lower quality settings usually create smaller files but may soften fine details. At balanced settings, the difference is often difficult to notice at normal viewing size. PNG output uses lossless compression, so its quality slider is disabled.
The tool accepts JPG, JPEG, PNG, and WebP images. It can export WebP, JPG, PNG, or keep the original supported format.
PNG and WebP can preserve transparency. JPG does not support transparency, so transparent areas are filled with white when JPG output is selected.
This can happen when the original file was already optimized, when PNG output is selected, or when converting a small JPG or WebP file into a less efficient format. Try WebP, reduce the quality, or use smaller dimensions.
No. Images are processed locally in the browser and are not uploaded to Toolisto or saved by WordPress.
Yes. The interface adapts to modern phones and tablets. Processing speed depends on the image size and available device memory.
Yes. The tool is free to use and does not require an account.