Image Compressor
Reduce an image's file size with a quality slider and optional downscaling, and see the real saving before you download.
Convert with this tool
or choose a file from your device — it is processed in this tab and never uploaded
Accepted: JPEG, PNG, WebP, GIF, AVIF, BMP
Files stay on your device. There is no upload, no queue and no watermark, so a conversion works even with the network switched off after the page has loaded.
Supported formats & processing
| Accepted input | JPEG, PNG, WebP, GIF, AVIF, BMP |
|---|---|
| Produced output | JPEG, PNG or WebP at a reduced size |
| Processing | Web Audio API + canvas + native JavaScript encoders |
| Upload required | No — the file is read locally and never transmitted |
How to use this tool
- Add the image and note the original sizeIt is shown next to the file name and again in the result card.
- Start with the quality slider around 80%That is usually visually identical to the original for photographs.
- Downscale if the image is larger than it needs to beA 4000 px photo displayed at 800 px can be resized to 1200 px with no visible loss.
- Choose the formatWebP often beats JPEG by a third at the same perceived quality.
- Convert and check the savingIf the output grew, lower the quality or change the format and try again.
About this tool
Image weight is usually the single largest contributor to a slow page. A photograph straight out of a phone camera is often 3–5 MB, and most of that is detail nobody will ever see at the size it is displayed.
This compressor works on the two levers that matter: the quality setting, which tells the encoder how aggressively to discard fine detail, and the dimensions, because halving the width removes three-quarters of the pixels. The result card reports the original size, the new size and the percentage saved, and it tells you honestly when the output has grown rather than shrunk.
Features
- Real re-encoding with a quality slider, not a metadata trick
- Optional downscaling in the same pass for compounding savings
- Original size, new size and percentage change all reported
- Honest warning when the output is larger than the input
- WebP output for the best size-to-quality ratio on the web
- Transparency preserved when you keep PNG or WebP
Frequently asked questions
How much can I compress without seeing a difference?
For photographs, a JPEG quality of 75–85 percent is usually indistinguishable at normal viewing size. Below 60 percent, smooth gradients such as skies begin to show blocking.
Why did my compressed PNG get bigger?
PNG is lossless, so a quality slider has no effect on it and the re-encode can add bytes. Switch the output format to JPEG or WebP for a photographic image.
Does compressing remove EXIF data?
Yes. Re-encoding through a canvas writes a new file with no metadata, which also strips GPS coordinates and camera information — often a privacy benefit when posting images publicly.
Should I resize before or after compressing?
Both happen in one pass here. In general, resize first in your head: reducing the dimensions removes more bytes per unit of visible quality than lowering the quality setting alone.