Image Compressor — Compress JPG, PNG, WebP & More, Free

Lossy vs Lossless Compression

Lossless compression (PNG) shrinks a file by encoding pixel data more efficiently, without discarding any information — decompressing it gives back an exact pixel-for-pixel copy. It's ideal for screenshots, logos, and graphics with sharp edges or text, but it rarely shrinks a photograph very much. Lossy compression (JPEG, WebP, AVIF) discards visual detail that's hard for the human eye to notice, which is why a photo can shrink by 70–95% and still look essentially identical on screen. Most everyday compression — for websites, email, and social media — should be lossy; reach for lossless PNG only when you need pixel-perfect accuracy, like a logo with flat colors or a screenshot with fine text.

Image Formats Explained: JPG vs PNG vs WebP vs AVIF

JPG/JPEG is the universal format for photographs — small, lossy, no transparency. PNG is lossless with full transparency support — best for graphics, logos, and screenshots, but larger for photos. WebP is a modern format that supports both lossy and lossless modes plus transparency, typically 25–35% smaller than an equivalent JPEG or PNG at the same visual quality, and is now supported by every major browser. AVIF is the newest format, often 20–50% smaller again than WebP at comparable quality, but browser and software support is still catching up — some tools and older devices can't open it yet.

Choosing the Best Compression Settings

There's no single "correct" quality setting — it depends on what the image is for. As a starting point: use Balanced (≈75% quality) for general web and social use, Maximum Compression (≈40%) when file size is the priority and the image will be viewed small (thumbnails, previews), and High Quality (≈90%) for print, portfolios, or any image where fine detail matters. If a platform or form specifies an exact size limit, switch to Custom mode and enter that number in the target-size field instead of guessing a quality percentage.

Compressing Images for Websites, Email, Social & E-commerce

For websites, compress hero and banner images to roughly 100–300 KB and thumbnails under 50 KB — this directly improves load time. For email, keep attachments under 500 KB each so inboxes stay fast on mobile data. For social media, most platforms re-compress on upload anyway, but starting from a 200 KB–1 MB file keeps more of your original detail than letting the platform's own aggressive algorithm decide. For e-commerce product photos, aim for the smallest file that still shows texture and color accurately at typical zoom — usually WebP at Balanced or High Quality, since shoppers judge product quality from these images directly.

Metadata Removal & Transparency Preservation

Every photo from a phone or camera carries EXIF metadata — camera model, exposure settings, and often precise GPS coordinates of where it was taken. Redrawing an image through a canvas (as this tool does) strips all of that automatically, along with embedded ICC color profiles, which is both a meaningful privacy improvement and a small extra size saving. Transparency is handled the opposite way — carefully preserved: if your source PNG or WebP has an alpha channel, this tool detects it and keeps output in a transparency-capable format (PNG or WebP) unless you explicitly choose JPEG, which has no alpha channel and will fill transparent areas white.

Browser-Based Compression vs Uploading to a Cloud Tool

Many popular compressors work by uploading your image to a remote server, compressing it there, and sending the result back — which means your file (and any metadata, including location data, still attached) briefly exists on someone else's infrastructure. Browser-based compression, using the Canvas API the way this tool does, skips that step entirely: the image is decoded, redrawn, and re-encoded using your own device's processor, and it's technically impossible for the file to leave your machine during that process. The tradeoff is that some advanced codec options (like true AVIF encoding on unsupported browsers) aren't available everywhere — this tool is upfront about that instead of pretending otherwise.

Batch Compression & Mobile Usage

Add as many images as you like in one go — each is compressed sequentially with the same mode and settings, so a folder of vacation photos or product shots can be processed in one pass instead of one file at a time. On mobile, the same interface works with your phone's photo library and file picker; there's no separate app to install, and the results stay on your device just like on desktop.

Best Practices & Common Mistakes

• Always compress from the original, highest-resolution file — re-compressing an already-compressed JPEG stacks quality loss.
• Resize before compressing when the display size is much smaller than the original (e.g. a 4000px camera photo shown at 800px wide) — it usually beats compression alone.
• Use WebP instead of PNG when you need transparency but file size matters — it compresses far more aggressively while keeping the alpha channel.
• Don't over-compress images with fine text or sharp lines (screenshots, diagrams) — artifacts show up fastest there; use High Quality or PNG for these.
• Keep an original, uncompressed copy — lossy compression can't be reversed once detail is discarded.