Compress JPG, PNG and WebP images in your browser. Adjust quality, pick an output format, compare the sizes and download the result. Your original file is never changed.
Compressed copies do not keep metadata such as camera details or GPS location. Your original files are never changed.
Your browser opens each image, draws it onto an invisible canvas and writes it out again in the format you chose. JPEG and WebP are lossy: the quality value tells the encoder how much detail it may throw away, so a lower number gives a smaller file and a softer picture. Because the file is re-encoded, a lower number is not a guarantee. Some images, such as screenshots and flat graphics, can come out the same size or bigger.
PNG works differently. A browser's PNG encoder is lossless, so there is no quality setting to turn down and the slider is switched off for PNG output. The ways to make a PNG smaller here are to lower the Max dimension, which removes pixels, or to change the output format to WebP or JPEG. This tool does not reduce the number of colours.
Max dimension limits the longer side of the image and keeps the proportions. Images that are already smaller than the limit are left at their size, never enlarged. Photos that were taken rotated are drawn upright, so they do not come out sideways.
After each run the tool compares the new file size with the original and tells you plainly whether the result is smaller, about the same, or larger. A difference of up to 0.5% of the original size is reported as about the same.
Reduction (%) = (original size - compressed size) / original size x 100 Scale = max dimension / longer side (applied only when the longer side is bigger) New side = round(side x scale) Encoder quality = slider / 100 (JPEG and WebP only; PNG ignores it)
A 4000 x 3000 photo is 12 megapixels. With Max dimension set to 1920 px the longer side becomes 1920 and the shorter side 3000 x 1920 / 4000 = 1440, so the result is 1920 x 1440. That is 2,764,800 pixels, about 23% of the original pixel count. How much smaller the file gets depends on the picture and the format you choose.
Suppose a 2,400,000 byte file (2.29 MB) is re-encoded to 600,000 bytes (585.94 KB). The saving is 1,800,000 bytes (1.72 MB), and 1,800,000 / 2,400,000 x 100 = 75.0%, so the card shows 75.0% smaller. These sizes are round numbers chosen to show the arithmetic, not a typical result.
Suppose a 100,000 byte file (97.66 KB) comes out at 130,000 bytes (126.95 KB). The card shows 30.0% larger, adds a warning, and relabels the button Download anyway. Try a lower quality, a different format or a smaller Max dimension, or keep the original.
No. The images are opened, resized and re-encoded by your own browser, and the tool does not send them over the network. Your original files are only read, never changed.
PNG is a lossless format and browsers do not offer a quality setting for it, so the slider is disabled instead of pretending to work. To shrink a PNG, lower the Max dimension or switch the output to WebP or JPEG.
The original may already have been compressed more tightly than your settings allow, which is common with files from design tools or other optimisers. The card warns you when this happens, so try a lower quality, a different format or a smaller Max dimension.
No. The compressed copy is written fresh from the pixels, so EXIF details like camera model and GPS location are not carried over, and your original colour profile is not kept (a standard sRGB profile may be added). The picture still comes out the right way up.
JPEG cannot store transparency, so transparent areas are filled with white and the card shows a note when your image has a transparency channel. Choose WebP or PNG to keep transparency.
The tool checks whether your browser can actually write WebP files and disables that option if it cannot. Images that were already WebP are then saved as JPEG, or as PNG if they have transparency, and the card tells you so.