Free Image Compressor Online – Compress JPG, PNG & WebP

Free browser tool · No API key

Compress Images Online for Free

Reduce image file sizes and choose the exact output dimensions you need. Convert JPG, PNG and WebP in your browser, compare the result and download your optimized image. Files are processed locally on this page.

WebP is the default because it is often smaller. PNG is usually lossless and may not reduce file size. JPEG does not support transparency.

A lower quality usually creates a smaller JPEG/WebP. PNG ignores this slider. Start around 70–80% and check the preview.

Choose a preset or enter custom width and height. With aspect ratio on, changing one dimension adjusts the other.

Privacy: Your selected image is processed in your browser using the Canvas API; this tool does not upload the image to our server and does not need an API key.

How to compress and resize an image

  1. Choose a photo or drag it into the upload area.
  2. Select WebP, JPEG or PNG as the output format.
  3. Choose a preset dimension or enter a custom width and height.
  4. Keep the aspect ratio enabled to avoid stretching the image, unless you specifically want to crop or distort it elsewhere.
  5. Adjust quality, click Compress image, then compare the new size and preview.
  6. Download the result only after checking its dimensions and visual quality.

Why can a compressed image become larger?

Some source files are already highly optimized. PNG can be larger than a source JPEG, and re-encoding to the same format may add overhead. This tool now defaults to WebP at 75% quality, offers explicit dimension presets, and reports when the result is larger instead of claiming it was compressed. If the output is larger, try WebP, lower the quality, or reduce the dimensions.

Choosing image dimensions for a website

Resize images to fit the space where they will appear. A blog thumbnail may not need a 4000-pixel original; a wide hero image may need a larger width. Common presets are provided as convenient starting points, but use your theme’s actual display dimensions where possible. Reducing pixel dimensions often saves more space than quality changes alone.

WebP vs JPEG vs PNG

WebP

WebP supports transparency and lossy or lossless compression, and often creates smaller web images. It is the recommended starting format for many website photos.

JPEG

JPEG is widely compatible and useful for photos. It does not preserve transparent backgrounds.

PNG

PNG works well for screenshots, logos and transparent graphics. Its output may be larger, so compare file sizes before replacing the original.

Frequently asked questions

Can I compress images without an API?

Yes. This tool uses the browser’s Canvas API, not a third-party image compression API.

Can I set a custom image size?

Yes. Choose Custom dimensions and enter the width and height in pixels. Keep aspect ratio selected to automatically calculate the other dimension.

Will every image become smaller?

No. Results depend on the source image, format and dimensions. If the output is larger, try a different format or smaller dimensions, or keep the original file.