Image Compressor
Drag a photo in, pick a target file size (2 MB, 500 KB, whatever the form will accept), and the tool finds the best quality that fits. JPG, PNG and WebP, multiple files at once, no upload, no sign-up. Your photo never leaves your browser.
Explain like I'm 5 (what this does)
You have a photo that is too big to send. You drop it in. You say how small it needs to be. The tool keeps trying slightly smaller versions until one fits, then hands you back a download. The original is untouched and the file never leaves your device.
Compress
Results
| File | Original | Compressed | Saved | Dimensions | Download |
|---|---|---|---|---|---|
| — | — | — | — | — | — |
Total saving will appear here once you compress.
Prove it
For target file size, the tool binary-searches the canvas encoder quality between 0.4 and 0.95, up to eight iterations. If even quality 0.4 stays over the target, it shrinks the longest side by 10% and retries, up to four shrinks. Encoding uses canvas.toBlob() with the chosen MIME type. Nothing is sent to a server.
Useful? Press Ctrl + D to bookmark.
Why people compress photos in the first place
Almost nobody compresses an image because they want to. They compress because some upload box is rejecting their 8 MB phone snap. Recruitment portals cap CV photos at 2 MB. Government forms cap supporting documents at 5 MB. Forum avatars want under 100 KB. Old corporate email systems still cough up at attachments over 10 MB. The need is always the same: take a perfectly nice photo and make it small enough to slip past the bouncer.
That is what this tool is for. Pick a target, drop the file in, get a smaller file out. The clever bit is finding the highest quality that fits, so you do not throw away more pixel data than you have to.
JPG, PNG and WebP, briefly and honestly
JPG is lossy and was designed for photographs. It is brilliant at smooth gradients (skies, skin tones) and rubbish at sharp edges and text. For a holiday photo at quality 0.8, JPG is usually the right answer.
PNG is lossless. The pixels you put in come out identical. That makes it ideal for screenshots, diagrams, logos and anything with hard edges, but the file size on a photographic PNG is usually three to five times the equivalent JPG. If you have a PNG of a photo that needs to be smaller, the most useful thing you can do is convert it to JPG.
WebP is Google's modern format, supported in every current browser. It typically gives JPG-like quality at 25 to 35% smaller files. The catch is older software (a 2018 Outlook install, say) might not open WebP, so use it where you control the destination.
What "quality" actually means
The quality number on a JPG or WebP encoder is not a percentage of how good the photo looks. It is a knob on how aggressively the encoder is allowed to throw away high-frequency detail. At 0.95 it barely throws anything away and the file is large. At 0.4 it throws a lot away and the file is small but blocky. The sweet spot for most photos sits between 0.7 and 0.85: you keep something close to 95% of perceived quality at roughly half the file size of the maximum-quality version. Below 0.6, you start to see blockiness in flat colour areas. Print work needs 0.85 or higher; screen work is happy at 0.7.
Dimensions matter more than quality, usually
Here is the bit most online compressors do not say out loud. A 4000 by 3000 photo saved at quality 0.95 is bigger than the same photo at 1920 by 1440 at quality 0.85, and on a screen you cannot tell them apart. If you are sending a photo to be looked at on a phone or a laptop, capping the longest side at 1600 to 2000 pixels is the single biggest lever you have. Quality is the fine adjustment after that. The "cap longest side" option in the form does this in one step.
Privacy: nothing leaves your browser
Most "free online image compressor" sites upload your file to their server, compress it there, and hand it back. That means every passport scan, child's school photo or confidential product shot you compress sits on someone else's hard drive for at least a moment. Some of those services keep copies for "improving the service". Some have been breached. Some quietly train models on the uploads.
This tool does the entire job inside your browser tab using the standard Canvas API. There is no server. You can disconnect from the internet halfway through and it will still finish. Open your browser's dev tools and watch the network tab if you want to check.
What this tool does not do
- It does not compress RAW camera files (.cr2, .nef, .arw, .dng). Those need dedicated software like Lightroom or darktable. Convert to JPG first, then compress here.
- It does not compress PDFs. PDF is a different beast, with text, vectors and embedded fonts. There are dedicated PDF compressors for that.
- It does not compress GIFs. Animated GIFs need a frame-aware tool like ezgif. A still GIF can be converted to PNG and brought here.
- It does not strip EXIF metadata as a feature. Re-encoding usually drops it as a side effect, but if you need guaranteed metadata removal for a sensitive photo, use a dedicated EXIF stripper.
Related calculators
Other browser-only image bits and pieces.
Frequently asked questions
How do I compress an image to under 2MB?
Drop the image in, choose Target file size, type 2 MB, and press Compress. The tool finds the highest quality that fits by binary-searching the JPG or WebP quality between 0.4 and 0.95. If the photo is so large that even minimum quality stays over 2 MB, it shrinks the dimensions in 10% steps until the file fits, and tells you what it changed.
How do I compress a photo for email?
For most modern mail, a 2 MB target is safe. For older work systems or recipients on dodgy connections, drop to 500 KB. While you are there, cap the longest side at 1600 pixels: a 4000-pixel-wide phone photo opened in a mail preview is wasted bytes.
Does compressing an image lose quality?
JPG and WebP are lossy, so technically yes. In practice, going from quality 0.95 to 0.75 usually halves the file size with no visible difference on a screen. Below 0.6 you start to see blockiness in skies and other flat areas. PNG is lossless: pixels in, pixels out, but the savings are much smaller.
Does this upload my files anywhere?
No. Compression runs entirely in your browser using HTML canvas. Nothing is uploaded, nothing is logged. Pull your network cable out mid-compress and it will carry on.
What is the best image format for small file size?
For photos, WebP wins, usually 25 to 35% smaller than JPG at the same visible quality. JPG is the safer choice if you do not control where the file ends up. PNG is for screenshots, logos and transparency, not for shrinking photos.
How do I compress a PNG?
If it is a photographic PNG, the honest answer is convert it to JPG or WebP. The tool offers a JPG override for PNG inputs for exactly this reason. If you need to keep transparency, stick with PNG output and reduce dimensions instead.