Free Image Compressor & WebP Converter

Compress images and convert them to WebP without uploading anything. Choose a format, quality and maximum width, drop in up to 20 images, and download smaller files that load faster on your website. All processing happens on your own device.

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Why image size matters

Images are usually the heaviest part of a web page. A single photo straight from a phone or camera can be several megabytes, many times larger than it needs to be for a website. Large images slow pages down, use visitors’ mobile data and often delay the biggest element on the screen, which affects Largest Contentful Paint (LCP), one of Google’s Core Web Vitals.

Faster pages keep more visitors. People leave slow pages, especially on mobile connections, and every second of loading time is a chance to lose a customer. Compressing and resizing images is one of the quickest, cheapest speed improvements available to almost any website.

Formats explained

  • WebP: a modern format supported by all major browsers. It typically produces noticeably smaller files than JPEG or PNG at similar visual quality. Recommended for most website images.
  • JPEG: the classic format for photos. Good compatibility everywhere; larger than WebP at the same quality.
  • PNG: lossless, ideal for screenshots, logos or graphics with sharp edges and text, but large for photographs.

If you are unsure, choose WebP at about 75–85% quality and a maximum width of 1920 pixels for full-width images, or 1200 pixels for images inside your content.

How to use the image compressor

  1. Choose the output format. WebP is selected by default where your browser supports it.
  2. Choose a resize option. Most images do not need to be wider than they are displayed on your site.
  3. Set the quality. Around 80% is a good balance; lower saves more space but can show artefacts.
  4. Drop images onto the box, or click it to choose files: JPG, PNG, WebP or GIF, up to 20 at a time and 25 MB each.
  5. Review the results: original size, new size, dimensions and the percentage saved.
  6. Download each image, or use Download all.

If a compressed file would be bigger than the original, which can happen with images that are already optimised, the tool keeps your original file instead.

Your images stay private

Many online compressors upload your files to their servers. This one does not. Images are decoded and re-encoded by your own browser, so photos of your customers, documents or unreleased products never leave your device. You can even use it offline once the page has loaded.

Worked example

A café in Sydney adds a new menu page with eight photos taken on a phone. Each photo is around 3–4 MB and 4000 pixels wide, so the page is very slow on mobile. In the compressor the owner chooses WebP, a maximum width of 1200 pixels and 80% quality. The photos come out at a small fraction of their original size and still look sharp on screen. After uploading the new versions, the menu page loads much faster on a phone.

Best practices for website images

  • Resize before uploading. Do not rely on your website to shrink huge images.
  • Use descriptive file names, such as chocolate-brownie-sydney-cafe.webp, not IMG_4032.jpg.
  • Always add alt text that describes the image for people using screen readers and for search engines.
  • Set width and height on images (most CMS platforms do this) to avoid layout shift while the page loads.
  • Lazy-load images below the fold, but not the main image at the top of the page.
  • Keep originals somewhere safe in case you need a higher-quality version later.

Common mistakes

  • Uploading full-resolution camera photos for small thumbnails.
  • Saving photographs as PNG, which makes them very large.
  • Compressing at very low quality, which makes products look cheap.
  • Generic file names and missing alt text.
  • Re-compressing the same image several times, which adds artefacts each time.

Tips for local businesses

For local businesses in the US, UK, Canada and Australia, real photos are powerful: your team, your premises, your work and your products help customers trust you. Compress them before adding them to your website and your Google Business Profile so they load quickly on phones, where most local searches happen. Use file names and alt text that describe the photo honestly, and mention the location only where it is genuinely relevant, such as a photo of your shopfront.

Frequently asked questions

Are my images uploaded anywhere?

No. Compression happens entirely in your browser. Your images never leave your device.

Does WebP work on all browsers?

All current versions of the major browsers support WebP. If you need to support very old systems, choose JPEG.

What quality setting should I use?

Around 75–85% works well for most photos. Check the result at full size; if you see blocky areas or banding, increase the quality.

Will compressed images still look good on retina screens?

Yes, if the width is about twice the size the image is displayed at. For an image shown 600 pixels wide, a 1200-pixel version is a good choice.

Can WordPress convert images to WebP for me?

Recent WordPress versions and many optimisation plugins can create WebP versions. Resizing and compressing before upload still reduces storage and gives you more control.

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