Batch image compressor
Shrink a whole folder of photos in one go.
Drop in as many images as you want, compress or convert them all, and download one zip. Set an exact target file size instead of guessing at a quality slider. Nothing you upload ever leaves your browser.
Drop images here, or browse files
JPG, PNG, WebP, HEIC-in-browser support varies by device — any image your browser can open
🔒 Runs entirely in your browser — your images are never uploaded anywhere
Output
PNG is lossless — quality and target-size settings don't apply to it.
Compression
Quality
Drop images in to get started.
0 / 0 images
✓ Compression complete
Original 0 B → Output 0 B
✓ Ready to download
A free batch image compressor that runs in your browser
Quantize compresses and converts whole folders of photos at once — no software to install, no files uploaded to a server. Drag in your images, pick a format, and download everything as a single zip in seconds. It works for product photos, blog graphics, portfolio images, or any batch of files you need smaller before uploading them somewhere else.
Hit an exact file size, not a guess
Most compressors make you drag a quality slider and hope. Quantize's target file size mode does the opposite: type the size you need — say, 500 KB for a form upload limit — and it automatically tests compression levels until the output lands at or under that number.
Convert between JPG, PNG, and WebP
Switch formats while you compress. Convert JPG photos to WebP for smaller web pages, flatten PNGs down to JPG when transparency isn't needed, or keep everything lossless in PNG. Presets for web, social, and email cover the most common size targets automatically.
Private by design
Every image is processed locally in your browser using the Canvas API — nothing is ever sent to a server, so there's no upload wait and no privacy concern with sensitive or personal photos.
Guides
How to reduce image file size without losing quality — the four levers that actually control file size, in order.
How to compress images to fit email attachment limits — getting a batch of photos under the 25MB wall most providers enforce.
JPG vs PNG vs WebP: which should you use? — a plain-language breakdown of when each format actually makes sense.
Best image format and size for a fast website — how oversized images slow down pages, and what to do about it.