Compress Images Online

Lossy, lossless and smart modes

Three compression modes cover the trade-offs. Lossy re-encodes with adjustable quality and is where most size savings come from. Lossless keeps pixel values intact and only trims encoding overhead, useful when a working PNG must stay exactly recoverable. Smart mode picks a balance automatically between size and visible quality. The output format selector keeps the original, or forces JPG (broad compatibility), PNG (lossless with transparency) or WebP, which is preselected because it usually produces the smallest file at the same visual quality.

Quality has four preset buttons: high at 95%, balanced at 80%, high compression at 60% and minimal at 40%; the slider underneath sweeps 10 to 100 directly (default 80). Lower numbers buy smaller files but introduce block artifacts in flat skies and soft banding in gradients.

• Start at the balanced 80% preset for photos; drop to 60% only for thumbnails and social previews.
• For screenshots and graphics with flat color, PNG or WebP at near-maximum quality usually beats low-quality JPEG.
• Recompress runs the same file again at a different setting; process new image swaps in the next batch; cancel stops an in-progress pass.

Hitting a target file size

The target file size field (1 to 20000 KB, optional) is the practical answer when a form, forum or marketplace demands a specific weight. Enter the cap and the tool iterates the encoding downward until the file lands at or under that number instead of you guessing a quality slider. Start from the target rather than from 40% quality, so the result keeps as much detail as the cap allows.

Before inlining an image in a page, remember the Base64 encoder adds about 33 percent on top of the compressed size, so compress first and encode second. When compression alone cannot shrink a photo because it is also the wrong format, the Format Converter swaps between JPEG, PNG, WebP and BMP as a separate pass.

Choosing the mode and format combination

For photos heading to the web, lossy mode with WebP output at the 80 percent preset is the default sweet spot: roughly a tenth of the file size of the original with no visible loss on mobile screens. Switch to 60 percent for thumbnails and previews, and stay at 95 when the image will be zoomed in a gallery. Lossless mode is for working PNGs where exact pixel preservation matters; smart mode is the hands-off choice.

JPG remains the safest choice for older systems and email attachments; PNG stays for graphics with transparency. The target file size field is the exact fit when a form lists a KB cap: enter it and the tool iterates the quality down automatically rather than you guessing. Recompress runs the same file again; process new image starts the next batch. Remember the Base64 encoder inflates the result by about a third, so compress before inlining.

Reading before and after sizes

The result view shows the original size next to the compressed size so the trade-off is explicit. If a result looks blocky, nudge the quality slider up a notch or move to the balanced 80 percent preset; if it is still above a portal's cap, re-enter the target KB and let the iterative pass find the lowest acceptable quality. Cancel stops a running batch cleanly.

How the Online Image Compressor Works

Large JPG, PNG and WebP files slow down websites, bounce mobile visitors and get rejected by portals with strict upload limits. PixlReady compresses images directly in your browser using adaptive, visually lossless encoding: it analyses each photo, removes redundant data and tunes quantization so the file shrinks dramatically while the picture still looks clean. Nothing is uploaded, so an entire folder of photos can be compressed as fast as your own device allows.

Choose from four quality presets (high at about 95 percent, balanced at 80 percent, high compression at 60 percent and smallest at 40 percent), keep the original format or convert to JPG, PNG or WebP, and process a single image or a whole batch that downloads as one ZIP. Photographic JPG and WebP files shrink the most; PNG screenshots and graphics with sharp text use lossless-style settings to stay crisp.

Tips for best results

• Pick the balanced preset first and compare the before/after size; only drop to high compression if the portal still rejects the file.
• Convert photos to WebP when the target website supports it; files are typically 25 to 35 percent smaller than JPEG at similar quality.
• Keep PNG for logos, screenshots and images with transparency, where JPEG artifacts would be visible.
• Compress after you resize; editing a large image down and then compressing yields the smallest, sharpest result.

Common use cases

• Speeding up a website or online store by shrinking product photos before upload
• Meeting email, visa, government and job-application file-size ceilings
• Reducing mobile data usage when sharing photo albums
• Preparing batches of blog or social media images in one run

Compression guides

• Compress an image to 200 KB — hit a common portal size cap without guessing
• Compress images for a website — keep pages fast without visible loss
• A TinyPNG alternative — same local compression, no upload queue

Frequently Asked Questions