Image Compressor
Drop in as many photos as you like, say how big each one is allowed to be, and get them all back in a ZIP. The tool finds the best quality that still fits your limit.
Drop in as many photos as you like, type the biggest size each one may be, and this free compressor finds the highest quality that still fits. It reduces the pixels first and only then compresses, so as little detail as possible is lost. Everything runs in your browser, so there is no upload and no daily limit.
Choose your photos
Drag them here, paste them, or tap to browse. Pick fifty at once if you like — they are all handled on your own device.
Making the picture smaller in pixels first keeps far more detail than squeezing the quality alone.
Add more photos
They join the list with the same settings.
Smaller files, with as little lost as possible
A phone photo is usually four to eight megabytes. Most school portals refuse anything over one, and a WhatsApp group mangles whatever it is given. This fixes both, in one go.
Drop the photos in
As many as you like. Nothing is uploaded, so there is no daily limit and no queue.
Set the limit
Type the biggest size each file may be, and optionally cap the longest side in pixels.
Press compress
Each photo is searched for the best quality that still fits, and you see exactly how much was saved.
Download
All of them as one ZIP, or any single one on its own.
Pixels first, then quality
There are two ways to shrink a photo: make it smaller in pixels, or compress it harder. Reducing a 4000 pixel photo to 1600 removes three quarters of the data and almost no visible detail, because nobody views it at full size anyway.
Squeezing the quality instead leaves the same number of pixels but makes each one messier, which is what produces blocky, smeared pictures. This tool resizes first and only then compresses, so it reaches your limit with the least damage.
Which format to choose
JPG is right for photographs and is what every form and portal accepts. WebP gives roughly a third smaller files at the same quality and every modern browser shows it, but a few older systems still will not.
PNG throws nothing away, so it is the one for screenshots, diagrams and logos with sharp edges — but a photograph saved as PNG will be much larger, not smaller.
What size do you actually need?
800 px is plenty for a thumbnail or a WhatsApp forward. 1280 to 1600 px looks sharp on any screen and suits a school website or a newsletter. 2048 px covers a projector.
Only go above that if the picture will be printed — a photo printed at A4 wants around 2500 to 3000 pixels along its long side.
Why doing it offline matters
Compression websites upload your originals, keep them for hours or days, and cap you at ten or twenty files unless you pay. For a school that means a hundred children's photographs sitting on somebody else's server.
Here the work is done by your own computer. There is no limit on how many files you pass through it, and nothing to delete afterwards.
Image Compressor — your questions
How do I compress an image to 50 KB?
Type 50 into the file size box, or press the 50 KB shortcut, and compress. The tool searches for the highest quality that still lands under your limit. If 50 KB is very tight for a big photo, also cap the longest side at 800 or 1280 pixels, which keeps far more detail than squeezing the quality alone.
Can I compress many photos at once?
Yes, and there is no cap on how many. Drop in fifty or a hundred, press compress once, and download the whole set as a ZIP. Compression websites limit you to ten or twenty files because each one costs them server time; here the work is done by your own computer.
Does compressing lose quality?
JPG and WebP do throw some detail away, which is how they get small. The tool reduces that loss by resizing first: a 4000 pixel photo cut to 1600 loses three quarters of the data and almost nothing you can see, because nobody views it at full size anyway.
JPG, PNG or WebP — which should I pick?
JPG for photographs and for anything a form or portal will accept. WebP for roughly a third smaller files at the same quality, which every modern browser can show. PNG only for screenshots, diagrams and logos with sharp edges — a photograph saved as PNG comes out larger, not smaller.
How many pixels wide should a photo be?
800 pixels is plenty for a thumbnail or a WhatsApp forward, 1280 to 1600 looks sharp on any screen and suits a school website, and 2048 covers a projector. Go above that only if the picture will be printed, where an A4 photo wants about 2500 to 3000 pixels along its long side.
Are my photos uploaded to a server?
No. Everything happens inside your browser on your own device. For a school that matters: a hundred children's photographs never end up sitting on somebody else's server waiting to be deleted.