Freedom251 › Image Compression Software
pngquant
What pngquant is
pngquant is a free command-line utility and native library for lossy PNG compression. Its site says conversion can reduce file sizes by as much as 70% while retaining full alpha transparency. Palette generation and adaptive dithering manage image quality, and a fast mode targets real-time processing or large batches. The tool supports batch processing and metadata controls, and generated images are described as compatible with web browsers and operating systems. The command-line program can integrate with shell scripts, graphical interfaces, and server-side software, including image pipelines, build tools, and CMS plugins. Native APIs cover C, Objective-C, C++, C#, and other languages able to call native code, with dedicated Java and Rust libraries. Quality settings range from 0 to 100, while speed ranges from 1 to 10; speed 10 is described as eight times faster than default with 5% lower quality. pngquant runs on iOS, Linux, macOS, Windows, and self-hosted setups. GPL or commercial licensing is available, and the licensing page says organizations generally need a commercial license.
Who it suits
pngquant suits developers and teams placing PNG compression inside scripts, applications, image pipelines, build tools, or CMS plugins. It is available for command-line and native-library workflows.
What it does well
- Can reduce PNG size by up to 70%
- Preserves full alpha transparency
- Supports batches and metadata controls
- Offers APIs for multiple programming languages
- Includes adjustable quality and speed settings
What to know first
- Only supports PNG input
- Lossy compression can trade image quality
- Organizations generally need commercial licensing
- Commercial licenses renew annually unless cancelled
Plans
| Plan | Billed and limits | Price |
|---|---|---|
| 11–50 | Annual · Organization size: 11–50 | $1,250 a year |
| 1,001–2,000 | Annual · Organization size: 1,001–2,000 | $15,500 a year |
| 51–200 | Annual · Organization size: 51–200 | $2,450 a year |
| 2,001–5,000 | Annual · Organization size: 2,001–5,000 | $25,500 a year |
| 201–500 | Annual · Organization size: 201–500 | $3,950 a year |
| 5,000+ | Annual · Organization size: 5,000+ | $49,500 a year |
| 2–10 | Annual · Organization size: 2–10 | $950 a year |
| Just me | Annual · Organization size: just me | $950 a year |
The first 8 of 9 plans, as pngquant.org lists them, read 11 Oct 2026. The maker's own page has the final word. Every plan
Verdict
pngquant is a focused PNG compressor with command-line, library, and integration options. Its free availability suits some users, while organizations should review the GPL and commercial licensing requirements.
Facts from pngquant's own pages
- Batch processing
- Yes · pngquant.org, 20 Sept 2026
- Commercial license
- The commercial license permits use in commercial products, internal tools, and customer-facing services, and annual licenses auto-renew unless cancelled. · supso.org, 11 Oct 2026
- Compatibility
- Generated images are described as compatible with all web browsers and operating systems. · pngquant.org, 11 Oct 2026
- Compression
- The site says conversion can reduce file sizes by as much as 70% while preserving full alpha transparency. · pngquant.org, 11 Oct 2026
- Compression modes
- lossy · pngquant.org, 20 Sept 2026
- Free plan
- Yes · pngquant.org, 20 Sept 2026
- Image quality
- It uses palette generation and adaptive dithering, and offers a fast mode for real-time processing or large batches. · pngquant.org, 11 Oct 2026
- Integrations
- The command-line tool can be integrated with shell scripts, GUIs, and server-side software. · pngquant.org, 11 Oct 2026
- Intended users
- The maker describes production use in image pipelines, build tools, and CMS plugins. · supso.org, 11 Oct 2026
- Licensing
- The project offers GPL or commercial licensing, and its licensing page says organizations generally need a commercial license. · pngquant.org, 11 Oct 2026
- Limits
- The CLI quality setting ranges from 0 to 100, and speed ranges from 1 to 10; speed 10 is described as eight times faster than default with 5% lower quality. · pngquant.org, 11 Oct 2026
- Metadata controls
- Yes · pngquant.org, 20 Sept 2026
- Platforms
- The site lists command-line binaries for macOS, Windows, and Linux; the library page also describes iOS and macOS Xcode projects. · pngquant.org, 11 Oct 2026
- Purpose
- pngquant is a command-line utility and library for lossy compression of PNG images. · pngquant.org, 11 Oct 2026
- Security
- The licensing page says purchase proceeds support security report responses, bug fixes, new features, and long-term maintenance. · supso.org, 11 Oct 2026
- Support
- The project asks users to submit bug reports or feature requests on GitHub. · pngquant.org, 11 Oct 2026
- Supported formats
- PNG · pngquant.org, 20 Sept 2026
- Supported interfaces
- The native library provides APIs for C, Objective-C, C++, C#, and other languages that can call native code, with dedicated Java and Rust libraries. · supso.org, 11 Oct 2026
Where pngquant stands on Freedom251
- Image Compression Software#37 of 85