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Image Compressor and Resizer

Shrink photos and images in bulk, resize them and convert to JPG, PNG or WebP — without uploading.

Settings

How to use

  1. Drop your images onto the box, or press "Choose images" and select one or more files.
  2. Pick an output format and move the quality slider. 70–85% is a good balance for photos.
  3. Optionally enter a maximum width or height to make large photos smaller. The aspect ratio is always kept.
  4. Check the new file sizes in the list, then download images one by one or all together as a ZIP file.

How image compression works

Digital photos store a color for every pixel, which adds up quickly: a 12-megapixel photo holds 36 million color values. Image formats shrink this in two different ways.

Lossy compression (JPG and lossy WebP) throws away detail that the eye is unlikely to notice — fine texture in busy areas and subtle color changes. The quality setting controls how much is discarded. Between about 70% and 90% the difference is very hard to see, while the file can be five to ten times smaller than an uncompressed image.

Lossless compression (PNG) keeps every pixel exactly. It works best on images with large flat areas such as screenshots, diagrams and logos, and badly on photos. That is why converting a photo from PNG to JPG often saves far more than any quality setting can.

Resizing makes the biggest difference

Phone cameras produce images around 4000 pixels wide, but a web page or email rarely shows images wider than 1200–2000 pixels. Halving the width and height leaves a quarter of the pixels, so the file shrinks to roughly a quarter before compression even starts. Enter a maximum width or height and the tool scales each image down to fit, keeping the original proportions. Images that already fit are not enlarged.

What happens inside your browser

When you add a file, a background worker in your browser decodes it, draws it at the new size with high-quality smoothing, and encodes it again with your chosen format and quality. Working in the background keeps the page responsive even with large batches. The original files are never changed — you always download new copies.

Because the browser does the encoding, results can differ slightly between Chrome, Firefox and Safari. Some browsers, including Safari, cannot create WebP files; there the WebP option is disabled. iPhone photos in HEIC format cannot be opened by most browsers; turn them into JPG with the HEIC to JPG converter first, then compress them here.

Choosing settings for common jobs

  • Email attachments: JPG, quality 75%, max width 1600 px.
  • Website images: WebP, quality 75–80%, max width matching your layout (often 1200–2000 px).
  • Online forms with a size limit (such as 100 KB or 1 MB): JPG, start at 80% and lower the quality or the maximum width until the new size in the list is under the limit. Resizing helps most: a phone photo scaled to 1200 px wide usually ends up well under 1 MB, while a 100 KB limit often needs about 800 px or less.
  • Screenshots with text: PNG, or WebP at 90% or higher to keep text sharp.

Privacy

Many online compressors upload your images to a server for processing. This one does not: your images stay on your computer or phone from start to finish. Re-encoded images also leave out the EXIF metadata, such as the camera model and the GPS location.

Frequently asked questions

Are my images uploaded to a server?

No. Your images are decoded, resized and re-encoded by your own browser. Nothing is uploaded, so the tool also works with private photos and keeps working offline once the page has loaded.

What quality setting should I use?

For photos, 75–85% usually looks the same as the original while being several times smaller. Go lower for thumbnails, and higher if the image contains small text or sharp edges.

Why did a file get bigger or stay the same?

Images that are already heavily compressed cannot always be made smaller. If the result is not smaller and you did not resize or change the format, the tool keeps your original file instead.

Should I choose JPG, PNG or WebP?

Use JPG for photos, PNG for screenshots, logos and images with transparency, and WebP when you want the smallest files for a website. All current browsers can display WebP.

What happens to transparent areas when I convert to JPG?

JPG does not support transparency, so transparent areas are filled with white.

Does compressing remove photo metadata?

Re-encoded files contain only the image, so camera details and the GPS location are not copied. Files marked "original kept" are your untouched original and still include them.

Can I make an image larger?

No. The size limits only shrink images. Enlarging cannot add detail and would make the file bigger, so images smaller than your limits keep their original size.

Why can't it open my HEIC photo?

HEIC is the default iPhone format and most browsers other than Safari cannot decode it. Convert the photo to JPG first, then compress it here.

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