How to Compress an Image

1. Choose an image. Select a JPG, PNG, WebP, or another supported image file.
2. Select a preset. Start with Best Quality, Balanced, Smallest Size, or Custom.
3. Adjust the settings. Change quality, output format, dimensions, or metadata options when needed.
4. Compare the images. Check the original and compressed previews for visible changes.
5. Download the result. Review the new file size and save the compressed image.

Image Quality and File Size

The quality setting controls how much image information is kept when a supported lossy format is created.

There is no single quality value that works for every image. Photos, screenshots, logos, and illustrations contain different types of detail.

Examples and Comparison: JPG, PNG, WebP, and AVIF

The output format can affect both file size and image appearance.

Choose a format based on how the image will be used. A format that works well for a photo may not be the best choice for a logo or screenshot.

Lossy and Lossless Compression

Lossy compression reduces file size by removing some image information. JPG and common WebP settings use this method. It can create a much smaller file, but the change cannot be fully reversed.

Lossless compression stores the image more efficiently without removing its pixel information. PNG is commonly used for lossless images. It can preserve sharp details and transparency, but it may not reduce photo file sizes as much.

The word “lossless” does not mean that the file will always be small. It only describes how the image information is stored.

How Image Dimensions Affect File Size

Width and height have a strong effect on image size because larger dimensions contain more pixels.

For example, an image measuring 4000 × 3000 pixels contains far more pixels than an image measuring 1200 × 900 pixels. If the image will only appear in a small webpage area, keeping the larger dimensions may not be necessary.

Enable the resize option when you want to limit the maximum width or height. The tool should keep the aspect ratio and avoid enlarging smaller images unless you choose otherwise.

How Transparency Is Handled

PNG, WebP, and supported AVIF output can keep transparent areas. JPG cannot store transparency.

If you convert a transparent image to JPG, the transparent areas must be replaced with a background color. White is a common choice, but you may select another color when the option is available.

Check the compressed preview before downloading because a background that looks correct on one webpage may not match another design.

Removing Image Metadata

Some images contain metadata such as camera details, software information, timestamps, orientation instructions, or location data.

The metadata option removes supported information when the output image is created. Not every format, browser, or encoder exposes or removes every metadata field.

Photos taken on phones may use orientation metadata. The image should be shown in the correct direction before that metadata is removed.

Why a Compressed Image Can Be Larger

A compressed result is not always smaller than the original. This can happen when:

• The original image was already compressed efficiently.
• A photo is converted from JPG or WebP to PNG.
• The selected quality is higher than the quality of the original file.
• The output keeps large dimensions that are not needed.
• The selected format is not suitable for the image content.
• The new encoder stores color or file information differently.

If the result is larger, try a lower quality, a different format, or smaller maximum dimensions. You can also keep the original file when the new result does not provide a useful improvement.

Use Cases: When to Compress an Image

• Websites: reduce the amount of image data visitors need to download.
• Email: create smaller attachments that are easier to send.
• Forms: reduce an image before uploading it to a portal with a file-size limit.
• Documents: reduce images before adding them to PDF files or presentations.
• Storage: save space when keeping many photos, screenshots, or graphics.
• Messaging: create smaller files for sharing on slower connections.

Use the separate Compress Image to KB tool when a form requires a specific limit such as 50 KB, 100 KB, or 200 KB.

Common Image Compression Mistakes

• Using very low quality immediately: start with a balanced setting and reduce it slowly.
• Using PNG for every photo: PNG files can be much larger for detailed photographs.
• Changing a transparent logo to JPG: JPG replaces transparency with a solid background.
• Enlarging a small image: upscaling can add blur and increase file size without adding real detail.
• Compressing the same JPG many times: repeated lossy compression can add more visible damage.
• Checking only the percentage saved: also inspect text, edges, faces, gradients, and transparent areas.
• Deleting the original too soon: keep the source file when you may need a higher-quality version later.

General Compression or Exact File Size?

Privacy, Browser Processing and File Data

Image decoding, previewing, resizing, and compression are designed to run in the browser for supported formats.

File names, image pixels, EXIF values, location details, previews, and downloaded file names should not be included in analytics events.

Large images may require significant browser memory. Processing can be slower on phones, older devices, or browsers with limited format support.

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