Does compressing change the file format?

No. A JPG comes back as a JPG, a PNG as a PNG, and so on. That is the point of this tool as opposed to the converters — if you want a different format, converting to WebP usually saves more than compressing the original.

Will my transparent PNG stay transparent?

Yes. Transparency is carried through untouched, and PNG compression here is entirely lossless — the result is pixel-identical to what you uploaded, just packed more efficiently. Nothing is ever flattened onto a background.

How much smaller will my images get?

For photographs straight from a camera or phone, typically 40–80% at the Balanced setting. Screenshots and graphics saved as PNG save less, often 5–25%, because they are already losslessly compressed and this keeps them lossless.

Why did one of my files come back the same size?

Because compressing it would have made it bigger. That happens with images that are already heavily compressed, and re-encoding them would cost quality for nothing. Rather than hand back a larger file, the original is returned untouched and reported as no saving.

Can I compress several images at once?

Yes — up to 20 in one job, each up to 50 MB. You can download each result on its own or take the whole batch as a single ZIP.

Are the image dimensions changed?

Not unless you ask. Compression works on how the pixels are stored, not how many there are. If the images are far larger than they need to be, the Resize option under Advanced will scale them down as well, which saves considerably more.

Is this converter free?

Yes. Every conversion on ConvertNicely is free to use, with no account, no watermark on the result and no limit on how many files you convert.

What happens to my files?

Your uploaded file is deleted from our servers the moment the conversion finishes, whether it succeeded or failed. The converted result is deleted automatically one hour later, and you can delete it yourself at any time with the Delete button.

Is there a file size limit?

Files up to 50 MB are accepted for this conversion. Larger limits apply to paid plans in future, but the free limit is generous enough for the overwhelming majority of JPG conversions.

Do I need to install anything?

No. ConvertNicely runs entirely in your browser and on our servers, so there is nothing to download or install. It works the same on Windows, macOS, Linux, Android and iOS.

Does it work on a phone?

Yes. The whole site is built mobile-first, so you can upload from your camera roll or files app, convert, and download the result without leaving your browser.

Free

Compress Images

Large images are the single biggest reason pages load slowly and email attachments bounce. This shrinks them in place: a JPG comes back a JPG, a transparent PNG comes back transparent, and the picture looks the same at normal viewing size. Add a batch at once and take them back individually or as a ZIP.

Also known as: image compressor · reduce image size · compress JPG · compress PNG

Files up to 50 MBTypically under a minute

Drop your files hereor choose a file from your deviceJPG, PNG, WebP, AVIF or TIFF · up to 50 MB · up to 20 files

Encrypted upload · deleted right after conversion

Your files are deleted automatically

Uploads are removed as soon as processing finishes, and converted files are deleted after 1 hour. Read our privacy policy.

How to compress images

Step 1
1. Add your files
Drag up to 20 JPG, PNG, WebP, AVIF or TIFF files into the box, or choose them from your device. Each can be up to 50 MB.
Step 2
2. Choose your settings
Adjust Compression (Balanced) and Remove metadata (on), or keep the starting values in brackets, which suit most files. More are under Advanced options.
Step 3
3. Press Compress Images
The work happens on our servers, and you can follow its progress.
Step 4
4. Download the result
Each file comes back in the format it went in; several come together in a ZIP. Your upload is already deleted, and the result is deleted after one hour.

Worth knowing

JPG, WebP and AVIF are compressed by re-encoding, which discards a little detail — invisible at Balanced for most photographs. PNG and TIFF are compressed losslessly, so they come back pixel-identical but save less. A file that is already compressed as far as your chosen setting allows is returned unchanged rather than made bigger.

Why compress images?

Getting photos under an upload limit for a form, listing or job application
Cutting page weight so a site loads faster and scores better on Core Web Vitals
Fitting a batch of images into an email attachment allowance
Freeing up storage on a phone or drive full of camera photos

What changes

What compress images changes, and what it leaves alone
Property	Before	After
Format	Unchanged	Unchanged
Dimensions	Unchanged	Unchanged
Transparency	Preserved	Preserved
File size	Original	Typically 40–80% smaller

Frequently asked questions

Page updated 3 October 2026

All Image converters

Compress Images

How to compress images

1. Add your files

2. Choose your settings

3. Press Compress Images

4. Download the result

Why compress images?

What changes

Frequently asked questions

JPG to WebP

PNG to WebP

JPG to PNG

HEIC to JPG

Compress Images

How to compress images

1. Add your files

2. Choose your settings

3. Press Compress Images

4. Download the result

Why compress images?

What changes

Frequently asked questions

Does compressing change the file format?

Will my transparent PNG stay transparent?

How much smaller will my images get?

Why did one of my files come back the same size?

Can I compress several images at once?

Are the image dimensions changed?

Is this converter free?

What happens to my files?

Is there a file size limit?

Do I need to install anything?

Does it work on a phone?

Related conversions

JPG to WebP

PNG to WebP

JPG to PNG

HEIC to JPG