Are my images uploaded?

No. Each image is decoded by your browser, drawn onto a canvas at the size you chose, and re-encoded with the browser's own JPEG, PNG or WebP encoder. Nothing crosses the network, which is why there is no daily limit, no file count tied to a plan, and no waiting behind other people's uploads.

Why does my PNG barely shrink?

PNG is lossless. The quality slider has nothing to throw away, so re-saving a PNG as PNG mostly changes how the same pixels are packed. Real savings on a PNG come from changing format: tick Convert PNG to WebP and a typical screenshot drops by 60 to 80 percent. If the PNG has transparency, WebP keeps it. Use WebP unless the file is going somewhere that only takes PNG.

What quality setting should I use?

80 is the default for a reason: on a phone or a normal monitor it is indistinguishable from the original and roughly half the size. Use 60 for thumbnails, chat and anything that will be shown small. Use 90 only for print or large hero images where you will zoom in. Below 50 you start to see blocks in gradients and skies.

Does it work on HEIC photos from an iPhone?

Only in Safari, which is the one browser that decodes HEIC. Everywhere else the tool will tell you it could not read the file. Export the photo as JPEG from Photos first (or turn on Most Compatible in the camera settings) and it will work.

Is there a limit on how many images I can compress?

Thirty at a time, up to 40 MB each, purely so the browser tab does not run out of memory. Download them, clear the list and drop the next batch. There is no daily cap because there is no server counting.

Free Tool

Image Compressor

Batch-compress JPEG, PNG and WebP in your browser. Set the quality, cap the width, convert PNG to WebP. No upload, no daily limit, no sign-up.

JPEG · PNG · WebP · GIFBatch of 30No uploadWorks in every browser

Drop images to compress

JPEG, PNG, WebP or GIF, up to 30 at once. Nothing is uploaded.

Quality 80

80 is invisible on a phone. Go to 60 for thumbnails and chat, 90 for print.

ResizeConvert PNG to WebPPNG is lossless, so the quality slider does nothing to it. WebP is where PNG savings come from.

Where the megabytes actually are

A photo from a current phone is around 4000 pixels wide and saved at quality 95. Almost nothing displays it that way: a YouTube thumbnail is 1280 wide, an Instagram post is 1080, a blog image is 800. So the first saving is not compression at all, it is resolution. Capping the width to 1080 throws away pixels no screen was going to show and cuts the file by three quarters before the quality slider has done anything.

The second saving is the quality setting, and 80 is the honest default. JPEG and WebP quality is not linear: from 95 to 80 the file roughly halves and nobody can see the difference at normal size; from 80 to 50 it halves again and you start to notice blocks in skies and gradients. Thumbnails and chat images can go to 60. Anything you will zoom into should stay at 90.

PNG is the exception that catches everyone. It is lossless, so a quality slider has nothing to remove, and re-saving a screenshot as PNG barely moves the number. The fix is a format change: WebP keeps transparency, decodes everywhere that matters, and typically shrinks a screenshot by two thirds. All of this happens in your browser through a canvas, so there is no upload, no queue and no daily cap, and the images stay on your machine.

Frequently asked questions

Quality, PNG versus WebP, and getting under a size

Drop it in, set quality to 60 and the resize to max 1080 pixels wide, then check the size in the list. A photo from a phone is usually 3 to 6 MB because it is 4000 pixels wide at quality 95; nobody views it that way. At 1080 wide and quality 60 the same photo is typically 80 to 150 KB. If it is still over, drop the quality to 50 or the width to 800.

More free tools

Video compressorThe same idea for video: hit a size limit in your browser, nothing uploaded.

Aspect ratio calculatorWork out thumbnail and cover dimensions before you export.

Safe zone checkerCheck where platform UI will cover your image or frame.

Media kit generatorPut the compressed images to work in a one-page media kit.

The full product

Smaller Images is just the start. Automate your whole faceless channel

Faceless generates the video and three AI thumbnails for it, rendered at YouTube's exact spec, then publishes everything to your channels on a schedule.