Image Compressor
Make photo files lighter and set the quality yourself
Your files stay with you. Conversion happens inside the browser; no file is ever uploaded to a server.
Did this tool do the job?
Thanks, your feedback came through.
How it works
Two levers do the work here, and they are worth understanding separately. The first is quality: JPEG encoding discards the detail your eye is least likely to register, and 75 percent is roughly where most photographs lose nothing visible while the file drops sharply. The second is the longest-edge limit, and on phone photos it is usually the larger win — pulling a 4000-pixel image down to 1920 removes three quarters of the pixels before the encoder even begins, because pixel count grows with the square of the edge. Used together they routinely take a 5 MB photo down to a few hundred kilobytes. Choose your files, set both values, press Compress: each result line reports the old size, the new size and the percentage saved, and that percentage is written into the file name as well.
This tool is also known as compress image, reduce photo file size, jpeg compressor, make a photo smaller in mb, shrink a picture for email.
What is Lossy compression?
Lossy compression makes a file smaller by permanently discarding information the eye is unlikely to register, and JPEG is the everyday example of it. The quality setting decides how much goes: between 75 and 85 most photographs show no visible change, while very low values bring out soft edges and blocky patches in skies and skin tones. What is thrown away never returns, which is why a compressed copy should be treated as an export for a particular purpose and never as the file you keep.
What is Lossless compression?
Lossless compression rewrites the same data in a more economical form and gives it back bit for bit — ZIP archives and PNG images both work this way. On photographs the payoff is modest, because millions of subtly different tones leave little repetition for the encoder to exploit. That is why shrinking a photo depends on the lossy path, while lossless methods earn their keep on screenshots, logos, diagrams and anything you may need to restore exactly as it was.
Lossy or lossless — which one actually shrinks a photo?
Lossless compression preserves every value and, on a photograph, trims only a modest slice off the file. Lossy compression discards what you were not going to notice and can take the same picture down to a tenth of its size. This tool is built for photographs, so it takes the lossy route and combines two levers: quality decides how much detail is thrown away, and the longest-edge limit decides how many pixels there were to begin with. When exact pixels or transparency matter — a logo, a screenshot, a diagram — do not send it through here at all; resize it instead and keep the lossless format.
How hard should you compress?
For email attachments and web pages, quality 70 to 80 with a 1920-pixel long edge is a sound starting point; at normal viewing size the difference from the original is not something you can point at. For anything headed to a printer, stay above 90 and remove the size limit, because print resolves detail that a screen hides.
Nothing here touches the source file. If a setting goes too far, change it and run the same photos again — the original sits on your device exactly as it was.
- Email attachment → quality 70, 1600 px
- Web page → quality 75-80, 1920 px
- Archive or print → quality 90 and above, no limit
Why the output is always JPG
The real saving on a photograph comes from lossy JPEG encoding. PNG is lossless and cannot come close on the same picture, so every file leaves here as JPG no matter what went in.
That has one consequence worth knowing in advance: transparency cannot survive. A PNG with a see-through background comes back with that area filled solid white. When the transparency matters, resize the picture instead of compressing it — resizing keeps the format and the alpha channel.
Frequently asked questions
How do I make a photo smaller without ruining it?
Keep the quality between 75 and 80 and cap the longest edge at 1920 pixels. On most photographs that pair is indistinguishable from the original at normal viewing size, while the file drops by a large margin.
How much did each file actually save?
The result line shows the old size, the new size and the percentage saved. The same percentage is written into the file name, so weeks later you can still tell which copy is the compressed one.
Is my original file changed?
No. A compressed copy is produced and the file on your device is left untouched, which is what makes it safe to try a setting, look at the result, and run the same photos again at a different value.
Why did my file get larger instead of smaller?
Two cases do that. The source may already be heavily compressed, so re-encoding it at a high quality setting adds data rather than removing it. Or it may be a screenshot or line drawing, which PNG stores far more efficiently than JPEG ever will.
Does a big drop in the long edge soften the photo?
When the long edge falls to less than half, the shrink is done with a detail-preserving resampling (the Lanczos method), so a 4000-pixel photo can become 1600 pixels with its lines and textures intact, and no jagged pattern is created for JPEG to spend bytes on afterwards. This does not replace the quality slider: below 50 percent the loss is visible anyway.