Image Compressor
Drop an image here or click to choose
Redraw one image as a JPEG at the same width and height. The quality slider, from 0.1 to 1, is what changes the file size. Transparency is not kept.
Read the guide: The image quality slider is not a file-size percent
How to use
- Drop one image, or click to choose it. The preview shows the original size in kilobytes and the pixel size.
- Move the slider. It starts at 0.8. Lower values make a smaller file and a blockier picture. The number is the JPEG quality passed to the browser, not a percentage of the original file size.
- Click Compress & Download. The file is named compressed.jpg. The line under the button shows the new size next to the old size.
What changes, and what does not
The image is drawn onto a canvas at its original pixel size, then saved as a JPEG. The dimensions do not change. A 4000×3000 photo stays 4000×3000. If you need fewer pixels, use Image Resizer first. Resizing is what helps when a site rejects a photo for being too many pixels, even after the file is smaller.
The output is always a JPEG, including when the input was PNG or WebP. PNG transparency is lost. On a transparent logo, the empty areas often turn black, because a JPEG has no alpha channel and the canvas starts transparent. Put the logo on a white background before you compress it, or do not use this tool for logos.
Photos shrink. Screenshots of text and flat UI colors often do not shrink much at 0.8, and they look worse if you push the slider near 0.1. A GIF is drawn as a still image, not as an animation.
One file at a time. If a HEIC photo shows no preview, the browser could not decode it as an image. Convert it with HEIC to JPG first.
A worked example
A 3.8 MB phone JPEG, 4000 pixels on the long side, at quality 0.8, commonly lands well under 1 MB and still looks fine in email. The pixel size is unchanged, so a form that says "maximum 2000 pixels" will still reject it. Resize first, then compress if the resized JPEG is still too large.
A 400 KB PNG screenshot of a receipt, with sharp black text on white, may come back almost the same size at 0.8, or even larger, because JPEG is a poor fit for flat text. Quality 0.5 will be smaller and the letters will halo. For a receipt you still need to read, keep the PNG or use a higher slider value and accept the size.
When not to use this
- The image is a logo or any PNG with transparency.
- You need to change the pixel dimensions. Resize first.
- You need to keep a GIF animation.
- The file is HEIC and the preview never appears.
Questions
Why is the download always named compressed.jpg?
The canvas export is a JPEG, so the name is fixed. Rename it after download if you need the original file name.
The new file is larger than the original.
The original was probably an already-small JPEG or a flat PNG. Raise the slider only if you need quality. If the new file is bigger, keep the original. This tool does not refuse a larger result.
Does 0.8 mean 80% of the file size?
No. 0.8 is JPEG quality. A photo might drop to a quarter of the size. A screenshot might barely change. Read the before-and-after line.