How to compress an image
- Drag your images onto the box above, or click to browse. You can add several at once, and every file gets the same settings.
- Choose an output format (JPEG or WebP) and drag the Quality slider. It runs from 10% to 100% and starts at 80%. Each row shows the original size, the new size and the percentage saved, and updates a moment after you stop dragging.
- Click Download on one image, or Download all to save the whole batch. Compressed files keep their original name with a
.jpgor.webpextension.
Why compress images?
Large images slow down websites, fill up storage, and are painful to email or upload. Compressing removes detail your eyes are unlikely to notice, which often cuts file size dramatically while the picture still looks the same. Smaller images mean faster pages and fewer rejected attachments.
What the quality slider actually does
Both output formats here are lossy. The encoder splits the picture into small blocks and rounds away fine detail that is hard to see, such as subtle colour differences and very high-frequency texture. A lower quality number means harsher rounding. The slider does not change the pixel dimensions: a 4032×3024 photo stays 4032×3024 pixels and only the amount of stored detail changes. If you also need fewer pixels, use the image resizer, because dropping dimensions saves far more than quality alone.
As a rough guide, savings are not linear. Going from 100% to 90% usually removes a large share of the file for almost no visible change. From about 80% down to 60% you start trading detail for size, and below about 40% blocky patches and colour banding become easy to spot, especially in skies and skin. Results vary by image: a noisy night photo shrinks less than a flat illustration. Judge by eye at 100% zoom on the picture you care about, not by the percentage alone.
JPEG or WebP?
JPEG works everywhere and suits photographs. WebP is a newer format that usually produces smaller files at similar visual quality and, unlike JPEG, can keep transparent areas. This tool paints a white background behind JPEG output, so a transparent PNG logo saved as JPEG gets a solid white box. Choose WebP if the transparency must survive. PNG files can be loaded, but there is no PNG output option, because PNG is lossless and cannot be shrunk by a quality setting.
Common mistakes
- Compressing the same file repeatedly. Each lossy save discards a little more detail and the damage accumulates. Always compress from the original, not from an earlier compressed copy.
- Expecting every file to shrink. If a JPG was already saved at a low setting, re-encoding it at 90% or 100% can produce a larger file. The savings figure then shows 0% and the new file is bigger than the original, so keep the original in that case.
- Compressing screenshots and text graphics as JPEG. JPEG blurs sharp edges and leaves faint halos around letters. For screenshots, flat graphics and logos, WebP at a high quality setting or the original PNG is a better choice.
- Judging at thumbnail size. Artifacts hide in the small preview but show on a full-size display or in print.
Practical targets
- Email and chat: aim for a few hundred kilobytes per photo so attachments stay under typical size limits.
- Website owners: a hero photo that is several megabytes is the most common cause of slow pages. Resize to the displayed width first, then compress at 70–80%.
- Online forms with a size cap: if a portal demands, for example, under 100 KB, lower the slider in steps and watch the live size. If quality alone is not enough, shrink the dimensions as well.
- Sellers and bloggers: batch a whole folder with one setting so every image on the site has a consistent size and look.
Limits of this tool
There is one quality setting for the whole batch, and no target-file-size mode, so reaching an exact size means adjusting the slider yourself. Processing uses your device's memory, so very large images may fail on older phones; try one image at a time. Because each image is redrawn and saved fresh, embedded metadata such as camera model and GPS location is not carried into the compressed file. That is useful for privacy, but copyright notes stored in metadata are dropped too.
Is it private and safe?
Yes. Unlike most online compressors, Toolyard does all the work inside your browser using your own device. Your images are never uploaded to any server, so nothing can be stored, seen, or leaked. You can even use it offline once the page has loaded.
Related guides
Read more: lossy vs lossless image compression, how to compress a JPEG without losing quality, JPG vs PNG vs WebP, or the compress image to 100KB tool.
Frequently asked questions
Does compressing reduce quality?
Yes, because both outputs are lossy, but at around 80% the change is hard to see at normal viewing size. Quality loss grows as you lower the slider, and it is permanent in the saved file, so keep your original. Raising the slider toward 100% keeps more detail but gives a larger file.
What formats can I compress?
You can load JPG, PNG and WebP images. Output is JPEG or WebP, the two lossy formats built for small files. PNG is not offered as output, since a quality slider has no effect on lossless PNG.
Why did my file get bigger instead of smaller?
This happens when the original was already compressed harder than your chosen setting, which is common with images from messaging apps or from other optimizers. Re-encoding at a higher quality cannot recover lost detail and may add size. Lower the slider, or keep the original file.
What happens to transparent backgrounds?
JPEG has no transparency, so transparent areas are filled with solid white. Select WebP as the output format if you need the transparency to remain. The result will then show a transparent background wherever the original had one.
Does it change the image dimensions?
No. The width and height in pixels stay exactly the same, and only the stored detail changes. To reduce the pixel dimensions as well, resize the image first with the image resizer and then compress it.
Is metadata such as GPS location kept?
No. The image is redrawn and saved as a new file, so EXIF data like camera model, date and GPS coordinates is not copied across. That helps when sharing photos publicly, but it also removes any copyright text stored in the metadata.
Is there a size or number limit?
There is no fixed limit. Because everything runs on your device, very large images depend on your computer's memory, but ordinary photos process almost instantly. If a huge file fails, try compressing it on its own.
Do you store my images, and is it free?
Never stored: files stay on your device and are not uploaded anywhere. The tool is completely free, with no watermarks, no account and no daily cap.