IMAGE COMPRESSOR
Shrink JPG, PNG and WebP file size online. Drag the compare slider, tune quality, and download when the balance looks right.
or click to browse — JPG, PNG, WebP
Before / after
Drag the slider to compare original and compressed preview
smaller files, same workflow
Oversized photos slow down websites, bounce email attachments, and blow past upload limits. OneImageTool compresses images in your browser — tune quality with a slider, compare before and after, and download when you are happy.
For the biggest savings on PNG sources, switch output to WebP or JPG. Use the quality slider and format options to balance size and clarity.
output formats
Pick the format that fits your workflow. JPG and WebP respond strongly to the quality slider; PNG keeps lossless transparency but may not shrink as much unless you convert to WebP.
| Format | Best for | Notes |
|---|---|---|
| JPG | Photos, general web images | Smallest files for photos; no transparency |
| WebP | Modern web, apps, CMS uploads | Great size/quality balance; transparency supported |
| PNG | Graphics with sharp edges or alpha | Lossless; use WebP if you need a smaller file |
three steps
Drop a JPG, PNG, or WebP. Original dimensions and file size appear instantly.
Move the quality slider and drag the compare handle to check detail. Switch output format if you need WebP or JPG.
Save the compressed file when the preview and file size look right.
where smaller files pay off
Images are usually the heaviest assets on a page. Compressing a 3 MB hero photo down to 300 KB cuts load time on slow connections and improves Core Web Vitals like Largest Contentful Paint — without swapping the image or changing your layout.
Attachment limits of 10–25 MB and upload forms that cap files at 2 MB are everywhere. A quality setting of 75–85 usually gets a photo under the limit while staying visually identical at normal viewing sizes.
Platforms re-compress whatever you upload. Sending a reasonably sized file gives their encoder less to destroy, so your listing photo or post often ends up looking better than if you had uploaded the raw camera file.
Screenshots and camera exports pile up. Re-encoding an archive folder as WebP at quality 80 routinely halves its size with no visible difference on screen.
know the limits
If a file was already compressed — a JPG saved from a photo editor at quality 70, or a WebP downloaded from the web — re-compressing it saves little and can stack visible artifacts on top of the ones already baked in. When savings look small in the stats panel, that is usually why.
Screenshots, text-heavy graphics and line art suffer at low JPG quality: sharp edges pick up ringing and smudge. For that kind of content, keep PNG, or use WebP at a high quality setting instead of pushing the JPG slider down.
The biggest single win is usually a photo saved as PNG. PNG is lossless, so photographic content stores far more data than it needs — switching the output format to WebP or JPG often cuts the file by 60–90% before you touch the quality slider. Very small files (under roughly 50 KB) are rarely worth optimizing further.
pick the right tool
Compressing re-encodes the same pixels with fewer bytes — width and height stay unchanged. If the image is genuinely larger than you need (a 4000px camera photo destined for an 800px slot), resize the image first; fewer pixels shrink the file more than any quality slider can.
Changing format is compression by another name. A photo stored as PNG shrinks dramatically when converted to WebP, transparency included — often a bigger saving than lowering JPG quality.
Processing a whole folder? The batch compressor handles up to five images at once and bundles them into a ZIP. And if you are preparing tiles for a social grid, split the image first, then compress the exported tiles so each one uploads quickly.
quick answers
Upload your image, adjust the quality slider, compare the preview, and download. The compressor runs entirely in your browser.
It depends on the source. Photos often shrink 40–80% as JPG or WebP at moderate quality. PNG sources compress less unless you convert to WebP or JPG.
No — this tool keeps the same pixel width and height. It re-encodes at lower quality to save bytes. Use Resize Image if you need smaller dimensions.
Upload JPG, PNG, or WebP. Download as JPG, WebP, or PNG.
No. Compression uses the canvas API in your browser. Your files never leave your device.
Yes — free, no watermark, no sign-up. Compress as many images as you need in a modern browser.
For photos, 75–85 is the sweet spot: files shrink 50% or more with no visible difference at normal viewing sizes. Below 60, JPG starts to show blocking around edges. For screenshots or graphics with text, stay above 85 or export as PNG.
Yes. Because the image is redrawn through the browser canvas, camera metadata such as GPS location, device model and capture date is not carried into the compressed file — a useful privacy side effect when sharing photos publicly.
