Compress Image to 100KB Free — No Upload, Works In Your Browser

1. 1Add your imagesDrag JPG, PNG or WebP files onto the drop zone, or select them with the Choose images button. You can add several at once.
2. 2Set a target sizeChoose Target size and enter the limit you need, such as 100KB for a form upload. Or switch to Quality to set the compression level directly.
3. 3Compress and downloadSelect Compress images, check the resulting size, then download each file individually or all of them together as a ZIP.

Compressing an image reduces its file size by storing the picture with less data. JPEG and WebP are lossy formats: they discard detail the eye is least likely to notice, such as fine variation in areas of similar colour. Lowering the quality setting discards more, producing a smaller file.

This matters because upload forms enforce hard limits. Government portals, job applications, university systems and forums commonly cap attachments at 100KB, 200KB, 500KB or 2MB, while a modern phone photo is 3–8MB. Compression brings the file under the cap without changing its pixel dimensions.

In Target size mode the tool performs a binary search over JPEG or WebP quality. It encodes the image, measures the result, and adjusts quality up or down until it finds the highest setting that still fits under your limit, typically within eight attempts. Everything happens in memory on your device.

If even the lowest quality cannot reach the target, the tool reduces the pixel dimensions in steps and retries, because a 4000-pixel-wide photo cannot reach 50KB by quality alone. When a target is impossible, the tool reports it rather than silently returning an oversized file.

Compression uses the browser's own canvas and image encoders. Files are read into memory, re-encoded locally, and offered back as a download. No image is sent to a server, which means nothing to breach, nothing retained after you close the tab, and no upload wait even for large batches. Once the page has loaded the tool keeps working with the network disconnected. Server-based compressors, by contrast, transmit and temporarily store your photo on someone else's machine.

A typical 12-megapixel phone photo of 4MB compresses to roughly 300–600KB at 80% JPEG quality with no visible change at normal viewing size, and to about 100KB at 40–50% quality with mild softening in fine detail. WebP generally produces files 25–35% smaller than JPEG at matched quality, though a few older applications still reject the format. PNG is lossless and compresses far less; converting a photographic PNG to JPG or WebP usually saves more than any quality setting. Screenshots and flat graphics are the exception and often stay smallest as PNG.