Image Compressor & Converter

No. The conversion uses a canvas in your own browser. Nothing is sent to a server, which is also why it works with no file size limit beyond your device's memory.

Set 'Target file size' to 'Exactly this size', type the number of KB, and pick JPG or PNG. The tool searches for the highest quality that fits under your number, then pads the file out so it lands on the figure precisely - 50 KB comes out as 51,200 bytes, not 49.4 KB. Use 'Under a size' instead when the form says 'must not exceed'.

The image is compressed to just under your target, then a few hundred harmless zero bytes are appended to the end of the file. Image decoders stop reading at the JPEG end-of-image marker and at the PNG IEND chunk, so those extra bytes change the file size without altering a single pixel. This is why exact mode is offered for JPG and PNG only: WebP and AVIF record their length in the container header, so padding them is not reliably ignored.

1024, because that is what the forms asking for '20 KB' mean. A 20 KB file from this tool is exactly 20,480 bytes.

Quality is lowered first, and if even the lowest quality overshoots, the image is shrunk in steps and tried again - a 1536px photo reaches 20 KB at around 983px wide. If the target is still impossible the row says so rather than quietly handing you a file that is too big.

WebP for almost everything on the web. Keep PNG only when you need lossless quality or transparency that WebP would not preserve well. For a form that demands an exact size, use JPG.