Image Compressor

How to compress an image online step by step

Start by clicking the upload box that says “Click to upload or drag and drop”, or drag a JPG, PNG, or WEBP file (up to 10MB) straight into it. As soon as the image loads, the tool shows the original preview with its file size and automatically compresses a first version at 80% quality.

Next, drag the “Quality” slider left or right to lower or raise the compression level, with the current percentage shown right next to the slider from 1% to 100%. Every time you move the slider, the “Compressed” image on the right is re-processed and its file size, along with the percentage saved compared to the original, updates instantly.

Once you are happy with the result, click the “Download Compressed Image” button to save the file to your device. The downloaded file is automatically named with a “compressed_” prefix followed by the original filename so it is easy to tell apart from the untouched image.

When to use it and the benefits

This tool is especially useful when you need to publish images on a website, blog, or social media, or attach them to an email that has a file size limit. Smaller image files load faster, improve user experience, and help with page speed scores in tools like Google PageSpeed, while also saving storage bandwidth.

It is also handy when you need to prepare a batch of product photos, blog illustrations, or profile pictures without installing heavy photo-editing software. All you need is a browser, and there is no waiting for files to upload to a server and then download the result, since everything happens locally.

Tips and things to keep in mind

A quality level around 70-85% is usually the sweet spot between a small file size and a sharp-looking image, which works well for photos used on the web. If the image is meant for print or needs to preserve fine detail, choose 90% or higher to avoid visible loss of sharpness when zoomed in.

Keep in mind that the tool always exports the compressed file as JPEG, even if the original was PNG or WEBP, so any transparent background in the source image will be flattened to white or black depending on the browser. If you need to keep transparency, consider a different format instead of running the image through this compressor.

You can try several quality levels by moving the slider repeatedly; each adjustment recompresses from the original image rather than compressing an already-compressed copy, so the quality calculation always stays accurate and consistent.

Privacy and free of charge

The entire compression process runs directly in your browser using canvas technology, and the original image is never sent to any VSM server or third party. That means private photos, sensitive documents, or personal pictures stay fully protected on your own device throughout the whole process.

The tool is completely free to use, with no limit on how many times you can use it and no account or sign-in required. You can come back and compress more images anytime at no cost.

Frequently asked questions

Does compressing an image online reduce its quality? Yes, since it uses lossy JPEG compression, but at a quality level of 70-85% the difference is barely noticeable to the eye while the file size drops significantly.

Is my image ever stored on VSM's servers? No, the whole process runs locally in your browser, and the image is never uploaded or stored anywhere outside your own computer.

Does the tool support PNG and WEBP files? Yes, you can upload PNG or WEBP images, but the compressed output is always exported as a JPEG file.

Can I compress multiple images at once? Currently the tool processes one image at a time; after downloading one result you can simply select another image to compress next.