MediaSlim

Per-image compression for macOS

On-device image compression for macOS. MediaSlim tunes each image separately for smaller files with a steadier quality floor. No uploads, originals stay untouched.

All features free · macOS 13+ · Apple silicon
CompressConvert
Add ImagesFolder
5 imagesSaved 78%
IMG_2043.HEICHEIC · 4.8 MB
4.8 MB1.4 MB
71%
Saved
release-shot.pngPNG · 5.5 MB
5.5 MB580 KB
90%
Saved
cover.jpgJPEG · 2.2 MB
2.2 MB610 KB
73%
Saved
portrait.pngPNG · 880 KB
880 KB240 KB
73%
Saved
scan-04.jpgJPEG · 3.3 MB
3.3 MB980 KB
70%
Saved
All done · 5 imagesSaved 12.4 MB · in Compressed folder
Show in Finder
CompressConvert
Add ImagesFolder

Drag images to start

Compression starts automatically · originals kept

Processed on your Mac · originals never modified
1 · Drag in2 · Done
Overview

Compress, or convert between formats

Compress

A per-image quality loop finds the smallest file that still looks right — not one fixed setting applied to everything.

Convert

Switch between the formats you actually use. Animated files are skipped entirely — never silently flattened to one frame.

JPEGPNGHEICWebP
Default output · measured Aug 2026

A steadier quality floor, image by image

JPEG · 30 public photos
Per-imagequality floor

Default output is essentially level with TinyPNG in total size (+0.30%); its lowest S2 is 74.47, versus 68.64 for TinyPNG.

JPEG · 8 multilingual mixed-content images
−11.03%total size

Risky mixed content automatically gets a higher quality floor; median S2 is 0.55 higher, with 7 of 8 images no lower than TinyPNG.

See the full benchmark →JPEG defaults updated 2026-08-15. TinyPNG is an evolving black box; figures apply only to the frozen output measured that day.
On-device

Nothing leaves your Mac

Compression runs entirely on your machine — no account, no upload, works offline.

Fully local

Every image is processed on your Mac — image data never leaves the device.

Originals kept

Output is written separately. Your original files are never overwritten.

Sensitive assets stay private

Design files, internal screenshots and client assets never touch a third-party server.

Try MediaSlim on your own images

Compression, format conversion, and Finder integration are all free. No account needed — install and start using MediaSlim right away.

Free · macOS 13+ · Apple silicon (arm64)