Compress any image to 1KB or less — the absolute minimum file size. Designed for the most extreme legacy portals and applications that enforce a 1KB image limit.
At 1KB, image dimensions must be very small for any recognisable result — typically under 50×50 pixels. Resize your image to the smallest acceptable dimensions before uploading. The tool cannot achieve good visual quality at 1KB from a large source image.
Drop your image onto the tool. The binary search algorithm finds the highest JPEG quality that keeps the file at or under 1KB. At this extreme target, the quality setting will be very low — expect heavy compression artefacts on anything larger than a tiny thumbnail.
Click Download to save the compressed image. Check the result carefully — at 1KB the output is suitable only for use cases that specifically require this size, such as legacy database icon fields or extreme bandwidth-constrained environments.
At 1KB, a JPEG image can represent approximately 32×32 to 50×50 pixels at low quality, or a tiny thumbnail at moderate quality. It is useful for favicon-style images, legacy database fields that store images as binary blobs with a 1KB cap, and certain extremely old CMS or portal systems. For any use case where the image needs to be recognisable at a larger display size, 1KB is not sufficient.
Heavily compressed. A 100×100 pixel image at 1KB will be at JPEG quality 1–5, showing significant blocking artefacts, colour banding and loss of fine detail. A 30×30 pixel image at 1KB can look acceptable because fewer pixels require less data. The comparison slider in the tool shows you the result before downloading.
Most modern portals use limits of 10KB, 20KB or 50KB at minimum because 1KB cannot represent a useful photograph at any standard display size. The 1KB target is primarily used for icon images, legacy database thumbnails, and technical use cases where image fidelity is not the primary concern.
Reduce the image dimensions to the absolute minimum needed for your use case before compressing. A 40×40 pixel image at 1KB can look reasonable. A 400×400 pixel image at 1KB will look terrible. The smaller the source dimensions, the more of the 1KB budget can be spent on quality rather than covering pixels.
PNG lossless compression cannot achieve 1KB for any meaningful photographic image. The tool automatically converts to JPEG for the compression step. If your use case requires PNG format, it will only be achievable at 1KB for extremely simple, low-resolution graphics such as solid-colour blocks or 16×16 pixel icons.
Yes — the binary search algorithm tests all quality levels from 1 to 100. If quality 1 still produces a file above 1KB, the image dimensions are too large. The tool will compress to the smallest possible size at quality 1 and report the final file size, even if it cannot reach exactly 1KB.
5KB allows significantly better quality than 1KB. At 5KB you can represent a 80×80 pixel image at good quality or a 150×200 pixel image at low quality. At 1KB, you are limited to very small dimensions or very poor quality at any larger size. If your portal allows 5KB, always use that target instead of 1KB.
Yes — signature images (black strokes on white background) compress extremely efficiently because they have very limited colour variation. A 140×60 pixel signature at 1KB is achievable and can look sharp enough for document submission purposes. Signatures are the best use case for the 1KB target.
