Compress an image
Re-encode a photo at a lower quality to make the file smaller.
Processed in your browser. This file is converted on your device and is never uploaded.
Converter
.png, .jpg, .jpeg, .webp up to 50 MB. You can also drag a file here.
No file selected.
About this tool
Most photographs can be made several times smaller with no visible difference, simply by re-encoding them at a sensible quality. This tool does that in your browser and lets you see the resulting file size before you keep it.
Only lossy formats are offered, because a quality setting is meaningless for PNG.
Supported formats and limits
- Input
- .png, .jpg, .jpeg, .webp
- Output
- .jpg (image/jpeg)
- Output name
- The original name with -compressed and the chosen format's extension, for example photo.png becomes photo-compressed.jpg.
- File size limit
- 50 MB
- Processing
- In your browser. The file is not uploaded.
How to use it
- Choose a .png, .jpg, or .webp file.
- Pick an output format and a quality level.
- Select Convert, compare the new file size with the original shown above it, and download the result.
Limitations
- Compression is lossy and cannot be undone. Keep your original.
- Re-compressing an already-compressed JPEG adds a second round of loss even at a high quality setting.
- Compressing an image that was already well compressed can make it larger, not smaller.
- Screenshots, logos, and line art compress badly with lossy formats and are better left as PNG.
- Metadata is not preserved, so EXIF and colour profiles are dropped.
- The image is not resized. Reducing the dimensions usually saves far more than lowering the quality, so consider the resize tool first.
Common problems
The file was refused before anything started.
Compress an image checks the extension before it reads a byte, and it accepts .png, .jpg, .jpeg, .webp. Browsers report file types inconsistently enough that the extension is what decides.
Rename the file if the extension is simply wrong, or convert it to one of those first. A file whose extension does not match its contents is refused for the same reason, and that one needs converting rather than renaming.
It said the file was too large.
The limit here is 50 MB. It is not a policy but a measurement: everything runs on your own device, and past that size a phone runs out of memory rather than finishing slowly.
Split the file, reduce it before converting, or use a desktop program for that one. A machine with more memory will manage more, but the limit does not know which machine it is on.
I selected several files and only one converted.
This tool takes one file at a time. Doing several at once would multiply the memory in use, which is the thing most likely to fail on a phone.
Convert them one after another. Nothing is kept between them, so there is no state to reset.
The tab reloaded itself part-way through.
The browser ran out of memory and restarted the page. At sizes approaching 50 MB this is the failure a phone hits first, and it looks like a crash rather than an error.
Try a smaller file, close other tabs, or run it on a computer. Nothing was uploaded or lost — the original file is untouched on your device.
The result opened in the wrong program.
The output is a .jpg file, and your system opens that extension with whatever it was told to. Nothing about the conversion decides it.
Open it from inside the program you want, or change the default for .jpg in your system settings. The file itself is correct.
Frequently asked questions
- Is my image uploaded?
- No. The compression runs entirely in your browser using standard canvas APIs. The image never leaves your device.
- Which quality should I use?
- 85% is a good default. Below about 70% the artefacts become visible on close inspection, especially around sharp edges and in smooth gradients such as skies.
- Why did the file get bigger?
- The original was probably already compressed harder than the setting you chose, or it is a graphic rather than a photograph. Try a lower quality, or leave it as it is.
- Would resizing help more?
- Usually yes. Halving the width and height removes three quarters of the pixels, which saves far more than any quality setting.
- Do I need to install anything or create an account to use Compress an image?
- No, to all of it. Compress an image runs inside the browser you already have, with no sign-up, no download, no watermark on the result, and no cap on how many files you convert. There is nothing to uninstall afterwards either, because nothing was installed.
- Does Compress an image work offline?
- Once the page has loaded, yes. The conversion runs on your device, so it needs no connection to do the work. The first visit fetches the page and the code that does the converting; after that a lost connection stops nothing, and a converted file appears exactly as it would online.
- How large a file can Compress an image handle?
- The limit is 50 MB. It is a deliberate one rather than a technical ceiling: the real constraint is memory, and a file that decodes to more than the device can hold fails in a way that is hard to explain. Phones run out well before laptops do, which is why the limit is set where it is.
- Can I convert several files at once with Compress an image?
- Not here: this tool takes one file at a time, because what it does depends on choices you make about that particular file. Convert them one after another, or look at the batch converters in the same category, which are built for a folder at a time.