Compress images without uploading them anywhere.

Why "where it processes" matters

Think about what people actually compress: passport photos, ID cards, signatures, medical documents, children's school photos, unreleased work. Uploading any of these to a free tool means a copy lands on someone else's server, under a retention policy you cannot verify and a jurisdiction you did not choose. "We delete files after 1 hour" is a promise; a file that never leaves your device needs no promises. For identity documents especially, the safest upload is the one that never happens.

How browser-local compression works

A web page is just code running on your machine. When you drop an image into SizeMint, your own browser decodes it, re-encodes it at the target size, and hands you the download — the same way a desktop app would, except there is nothing to install. The page itself is tiny (13KB of HTML, zero third-party scripts), so there is nowhere for your image to go even if it wanted to. No account exists to attach files to, and no server endpoint receives them.

Verify the no-upload claim yourself

Do not take our word for it. Your browser can show you exactly what leaves your device:

1. Open DevTools

Press F12 (or Ctrl+Shift+I on Windows/Linux, Cmd+Option+I on Mac) and switch to the Network tab.

2. Compress an image

With the Network tab open, drop a photo into the SizeMint compressor and run a compression. Watch the request list as it works.

3. Look for an upload

You will see the page's own small asset requests — and no image upload. No large POST request, no multipart form data carrying your photo. For contrast, run the same test on an upload-based compressor: you will see a multi-megabyte POST the moment you drop the file in. The difference is visible and unambiguous.

4. Try it offline (optional)

Once the page has loaded, you can even disconnect your network and compress — the core compression keeps working, because it never needed the network in the first place.

A note on EXIF metadata

Phone photos carry EXIF data — sometimes including GPS coordinates of where the shot was taken. Re-encoding an image in the browser strips this metadata: the encoder writes fresh pixels, not the original file's headers. You can confirm it with any EXIF viewer by comparing the original against the compressed download. Stripping location data is a side effect here, not a feature to rely on exclusively — for sensitive uploads, still check the file yourself.

What browser-local cannot do

Honesty matters here too. Browser-local compression cannot do server-side tricks like AI upscaling or huge batch queues that need datacenter GPUs. Very large images are bounded by your device's memory rather than a server's. What it does — compressing your images to exact target sizes privately — it does completely, with no account, no queue and no upload.

Frequently asked questions

How can a website compress without uploading?

The compression code runs in your browser, not on a server. Your browser already contains everything needed to decode and re-encode images — the website just orchestrates it locally.

Are my photos stored anywhere?

No. There is no account system and no storage — processed images exist only in your browser's memory until you download the result. Closing the tab discards them.

Does it work without an internet connection?

The page must load once (it is a website, after all), but compression itself needs no connection — you can verify this by going offline after the page loads and compressing anyway.

Is the compressed file really free of my location data?

Browser re-encoding drops EXIF headers including GPS. Verify with an EXIF viewer on the downloaded file — trust the check, not the claim.

Related guides

Compressing ID photos? Read how to reduce photo size to 100KB — written with document privacy in mind. Comparing tools on this exact criterion? See the honest TinyPNG-alternatives comparison.