Open source · batch image compressor

Shrink the file.
Not the photo.

Mass Image Compressor rips up to 90% off your image sizes and keeps every detail razor-sharp. Drop in a folder, walk away, and come back to a directory that loads instantly.

Download free See how it works // no account, no upload — it all runs on your machine
LIVE COMPRESSION PREVIEW coastline.raw
IN · 4.20 MB OUT · 0.53 MB
0.53MB output
from 4.20 MB source · JPEG q50
−87%
file size cut
Three steps, zero fuss

Drop it. Tune it. Done.

No queues, no cloud round-trips. The whole pipeline runs locally, so a thousand files finish while your coffee's still hot.

STEP 01

Drop a folder

Drag files or a whole directory onto the window. MIC walks every subfolder and lines up each image — including the RAW ones.

STEP 02

Tune the recipe

Pick an output format, dial quality against the live preview, resize, watermark, and choose which metadata gets to leave.

STEP 03

Export everything

Hit go. Progressive JPEGs, WebP, AVIF and retina sets land in your output folder, named exactly how you asked.

Built for people with too many images

Everything, in one pass.

Photographers, web teams and game studios all reach for the same tool — because it does the boring stuff perfectly and gets out of the way.

Whole folders, recursively

Point it at a directory and it compresses every image inside — subfolders and all — mirroring your structure on the way out.

Conversions that hold up

Class-leading JPEG→WebP, PNG→WebP and HEIC→JPG. AVIF on the way out when you want the smallest possible byte count.

Speaks fluent RAW

Feed it straight from the camera — Canon, Nikon, Sony, Olympus and most other raw formats go in without a converter in sight.

Animation, end to end

Animated PNG, WebP and GIF go in and come out with every frame intact — just lighter. Perfect for sprite sheets and loops.

Metadata on your terms

Keep EXIF, IPTC and XMP intact — or strip GPS coordinates and serial numbers before a single file leaves your desk.

Retina exports, done right

Accurate @1x / @2x / @3x sets from a single source, plus resize-to-print-size when you need real dimensions.

+ Progressive JPEG for faster first paint
+ ~30% smaller on stubborn PNG→PNG
+ Watermark whole batches at once
+ Prefix / suffix any output filename
+ Resize to a target print size
+ Skip if already compressed v4.2
In one end, out the other

If it's an image, it goes in.

Accepts

RAW JPEG PNG HEIC WebP GIF TIFF BMP CR2 · NEF ARW · ORF + more

Almost every popular format, plus the raw files from most Canon, Nikon, Sony and Olympus bodies.

Delivers

JPEG PNG WebP GIF AVIF

Modern, web-ready formats — progressive, animated or retina, whichever the job calls for.

Free & open source

Give your images
a crash diet.

Thousands of files, ninety percent lighter, not a pixel out of place.

// a community fork of Mass Image Compressor · licensed open source · runs 100% offline