Compress images – reduce file size
Photos too big for email, an upload form or your website? Drop them in, choose a quality or a target size, done. Images are compressed in your browser – no upload, no account.
How it is calculated
Phone photos are often 3 to 8 MB – too much for email attachments, upload forms with a size limit or fast-loading web pages. Compressing re-saves the image: details the eye barely notices are stored more coarsely and, if you like, the pixel dimensions are reduced. A photo usually shrinks to a fraction of its size without looking any worse.
How it works
- Drag images into the box, click to choose them or paste with Ctrl + V (up to 20 at once).
- Set the quality (default 75%) or switch to target size and enter e.g. 200 KB.
- Optionally limit the longest side – 1920 or 1280 pixels are plenty for websites and email.
- Download images one by one or all together as a ZIP file.
Which quality should I choose?
| Quality | Result | Good for |
|---|---|---|
| 85–95% | visually lossless | photo prints, portfolios |
| 70–85% | hardly any visible difference, much smaller | websites, email, social media |
| 50–70% | slight artifacts at edges and in gradients | thumbnails, uploads with tight limits |
| below 50% | visible blockiness | only when file size matters more than anything |
How much you save depends on the subject: a sky with a smooth gradient compresses far better than a photo full of leaves and fine patterns. The tool shows the size before and after for every image.
Compress to a specific size (e.g. 200 KB or 1 MB)
Many job application and government portals only accept images up to 200 KB, 500 KB or 1 MB. In target size mode the tool automatically finds the highest quality that keeps the file under your limit. If even a low quality isn’t enough, it scales the image down in 15% steps.
Automatic: the right format
With “Automatic”, JPG photos stay JPG. PNG images without transparency become JPG – often a fraction of the size for photos. PNGs with transparent areas become WebP, which keeps transparency: according to Google, lossy WebP images are 25–34% smaller than comparable JPGs. If re-saving doesn’t make an image smaller, the tool keeps the original.
Bonus: metadata is removed
Re-saving drops the EXIF data – camera model, capture time and often the GPS location. For images you share publicly, that’s a privacy win. The orientation (portrait/landscape) is applied first, so the image stays the right way up.
Privacy
Images are processed with your browser’s canvas API. Nothing is uploaded to a server; close the tab and all data is gone.
Frequently asked questions
Are my images uploaded?
No. Compression happens entirely in your browser. Your images never leave your device – once the page has loaded, it even works offline.
How do I compress an image to 100 KB or 1 MB?
Choose “Target size” and enter the limit in KB (1 MB = 1024 KB). The tool finds the best quality below that limit and only scales the image down if there is no other way.
Will the image lose quality?
JPG and WebP are lossy: fine details are lost each time they are saved. At 75–85% the difference is hard to see on screen. Always keep the original for editing.
Can I compress a PNG and keep transparency?
Yes: with “Automatic”, PNGs with transparent areas are saved as WebP, which supports transparency. JPG has no transparency; transparent areas are filled with the background color you choose.
How many images can I compress at once?
Up to 20 images of up to 50 MB each. “Download all as ZIP” gives you every result in one file.
Does it work with iPhone photos (HEIC)?
Yes. HEIC photos are decoded right in your browser (a decoder of about 2 MB loads once) and saved as JPG.
Why is my image larger after compressing?
That happens with images that are already heavily compressed, or at a high quality setting. The tool detects this and keeps the original file (“Original kept”).
Sources and legal basis
- ITU-T T.81 / ISO/IEC 10918-1 – JPEG
- W3C – Portable Network Graphics (PNG) Specification
- Google for Developers – An image format for the Web (WebP)
- AOMedia – AV1 Image File Format (AVIF)
- MDN – Image file type and format guide
- MDN – HTMLCanvasElement.toBlob()
- Open-source licenses of the libraries used (MIT, LGPL-3.0)
As of:
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