Reduce image file size with a quality slider and a live preview of the result before you download. Free, and it runs entirely in your browser — your photos are never uploaded. No account, no watermark.
Select an image and adjust quality
The Image Compressor reduces image file size using an adjustable quality slider, so you control the exact balance between smaller files and visual quality. Whether you're shrinking JPGs for faster web pages, lightening PNG screenshots, or trimming photos to fit an email, you drag the slider, preview the result live, and download, all in one place. Compression runs entirely in your browser with WebAssembly and Canvas, which means your images are never uploaded to a server and the tool works offline once loaded.
Compressing an image reduces the number of bytes it takes to store, usually by discarding detail the eye barely registers or by encoding the data more efficiently. The payoff is smaller files that upload faster, load quicker on web pages, fit inside email and form limits, and take up less storage, without changing the pixel dimensions unless you want them to.
A general-purpose compressor with a quality slider is the right tool when you don't have a strict size target but want the file meaningfully smaller. You decide how aggressive to be: nudge the slider down until the preview still looks clean, and you'll often cut file size by 60-80% with no visible difference.
There are two families of compression. Lossy compression (used by JPEG and WebP) permanently removes some image data to achieve much smaller files, and the quality slider controls how much it removes. Lossless compression (used by PNG) reorganizes data so nothing is thrown away, keeping the image pixel-perfect but limiting how small it can get.
The quality slider maps directly to this tradeoff for lossy formats. Higher settings keep more detail and larger files; lower settings shrink harder and eventually introduce visible artifacts like blocky patches or color banding. For most photos, a setting in the 70-85% range is the sweet spot where the file drops sharply but the image still looks essentially identical to the original.
Reducing file size solves a surprising number of everyday problems.
The right format depends on what's in the image. Photographs and anything with smooth gradients compress best as JPEG, which is built for natural images and shrinks them dramatically with little visible loss. Graphics with flat colors, sharp edges, or text such as logos, icons, and screenshots stay crisp as PNG, though the files are larger. WebP is the modern all-rounder, typically producing smaller files than JPEG or PNG at the same visual quality, and it's supported by every current browser.
Getting a small file that still looks good is mostly about matching the settings to the image.
All compression happens client-side in your browser, so your images are never uploaded and no server ever sees them. There's no account to create, no watermark on the output, and no limit on how many images you process. Once the page has loaded, it keeps working even without an internet connection, which makes it fast, private, and reliable for sensitive or bulk work alike.
It can, depending on how far you push it. Lossy compression permanently removes some data, but at moderate quality settings around 70-85% the loss is usually invisible while the file gets much smaller; only aggressive settings introduce noticeable artifacts. Lossless PNG compression loses no quality at all but produces larger files.
For typical photos you can often cut 60-80% of the file size with no visible difference, and more if you accept slight quality loss or resize the dimensions. The exact reduction depends on the image's content, its format, and how compressed it already is.
JPEG is best for photos and WebP is best overall when the destination supports it, since both use efficient lossy compression. Use PNG for logos, screenshots, and anything with text or sharp edges, where lossless compression keeps them crisp.
This compressor gives you a quality slider to control the tradeoff manually, which is ideal when you just want the file smaller. If you must hit an exact limit like 100 KB, use a compress-to-KB tool that targets a precise file size automatically.
No, compression reduces file size without changing pixel dimensions by default. You can optionally resize the image as well, which shrinks the file further and is often the most effective way to reach a very small size.
Yes. Every step runs inside your browser using WebAssembly and Canvas, so your images are never uploaded and no server receives them. That makes it safe for personal photos, documents, and anything confidential.
Yes, the compressor works with PNG as well as JPEG and WebP. PNG uses lossless compression so it stays pixel-perfect but shrinks less than JPEG; for photos saved as PNG, converting to JPEG or WebP usually produces a much smaller file.
No. The Image Compressor is completely free with no account, no watermark, and no limit on how many images you process. It also works offline once the page has loaded.
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