How to use the Compress Image tool
- Click Select images, drop files onto the box, or paste a screenshot with Ctrl+V. You can add up to 20 at once.
- Pick a quality. 75% is a good balance: most people cannot see a difference, and files usually shrink by 50–80%.
- Optionally choose an output format. Keep original keeps JPGs as JPG and PNGs as PNG; WebP usually gives the smallest file.
- Click Download next to each image, or Download all as ZIP.
Why compress images?
Photos straight from a modern phone are often 3–8 MB each. That is far more than most uses need, and big files cause real problems:
- Email attachments are usually capped at 20–25 MB in total, so a handful of photos can bounce.
- Websites load slowly when they use oversized images. Page speed is a Google ranking factor, and images are usually the heaviest part of a page.
- Online forms for jobs, visas and exams often reject files above 100 KB–2 MB.
- Storage and data: smaller files upload faster on mobile data and take up less space in cloud storage.
Compressing typically cuts a photo to a fifth of its size while it still looks the same on screen.
How image compression works
JPG and WebP are lossy formats. When you save at a lower quality, the encoder simplifies fine textures and subtle colour changes that our eyes are bad at noticing, and stores the result far more efficiently. The quality slider controls how much is simplified.
PNG is lossless: every pixel is kept exactly. It is the right choice for screenshots, logos and images with text or transparency, but for photos it produces large files. Converting a photo from PNG to JPG or WebP is often the single biggest saving you can make.
Choosing the right quality
| Quality | Typical use | What to expect |
|---|---|---|
| 85–95% | Printing, portfolios, product photos | Visually identical, moderate savings |
| 65–80% | Websites, email, social media | Best balance, large savings |
| 30–60% | Upload forms with strict limits | Some softness visible when zoomed in |
If you are unsure, start at 75%, check the result, and adjust. If a form gives you an exact limit such as 20 KB, use Compress Image to 20KB instead: it finds the right quality for you. And if the image is still huge in pixels, resize it first; fewer pixels shrink a file faster than any quality setting. The Apply settings again button re-processes all your images with the new setting, so you can compare quickly.
JPG, PNG or WebP?
- JPG works everywhere and is best for photos when you need maximum compatibility, for example uploading to older websites or government portals.
- PNG is best for screenshots, diagrams and images with transparent backgrounds.
- WebP is a modern format supported by all current browsers. It produces files around 25–35% smaller than JPG at the same visual quality and supports transparency, which makes it ideal for websites.
Your privacy
Most online compressors upload your photo to their server, process it there, and send it back. This tool does all the work inside your browser using built-in image technology, so your pictures never leave your device. That also makes it fast: there is no upload or download wait, even for large batches.
Frequently asked questions
Is it safe to compress private photos here?
Yes. The images are compressed by your own browser and are never uploaded to a server, so nobody else can see them. You can even disconnect from the internet after the page has loaded and the tool keeps working.
Will compressing reduce the quality of my photo?
JPG and WebP compression removes detail the eye barely notices. At 70–80% quality the difference is very hard to see on a phone or laptop screen. Go below 50% only when file size matters more than looks, for example for an upload form with a strict limit.
Why did my PNG barely get smaller?
PNG is a lossless format, so it cannot throw detail away. Screenshots and graphics often are already compact. If you need a much smaller file, choose WebP or JPG as the output format; WebP also keeps transparency.
What does 'already optimised, original kept' mean?
Sometimes an image is already compressed so well that re-saving it would make it bigger. In that case the tool gives you back your original file instead of a larger one.
How do I get an image under a specific size like 50KB?
Use the Compress Image to 20KB tool, where you can type any target size in KB. It finds the best quality that fits under your limit automatically.
Does it work on iPhone and Android?
Yes. It runs in Safari, Chrome, Firefox and Edge on phones, tablets and computers. iPhone HEIC photos are supported too and are converted on the fly.
Guide by the ToolsYes team · Last updated