OIMG

Compress images without losing quality.

OIMG uses state-of-the-art image compression techniques to reduce file size with minimal quality drop.

Download for macOS (Apple Silicon) or

Save storage

OIMG supports modern image formats that achieve substantial efficiency gains over popular formats like PNG and JPEG.

Storage

Lossless

Lossy

Target quality 90

Computed based on the CLIC 2024 image compression test set.

Open effortlessly

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The OIMG app window receiving an image via drag and drop.

The macOS Finder open-with menu showing OIMG as an available app.

A macOS terminal invoking OIMG from the command line with an image path.

Remain in control

OIMG computes in real time — so you can adjust proactively instead of experiencing unexpected quality drops.

Mount Fuji photographed at a distance under a pale sky.

Original

8.8

MB

Optimized

778

KB

50

99.2

Pixel match

92.8

MS-SSIM

62.9

SSIMULACRA

Find optimal thresholds

Explore the size vs. quality trade-off by visualizing quality metrics and compression efficiency on a graph.

Compatibility? No problem.

Convert back to JPG or PNG on demand with one click. (This is handy when uploading images to old websites!)

OIMG save-as JPG compatibility workflow.

Built for speed

OIMG is written in Rust for speed and memory safety, and utilizes multithreading and SIMD optimizations so that you can make the most of your time.

Private by design

OIMG makes zero network calls. All data stays local.

Free and Open Source

OIMG is free for personal and academic use forever, and is open sourced under GPLv3 license. Please contact [email protected] to discuss custom license arrangements.

Source code Issue tracker