Kraken.io From $4.17/mo · Free plan 9.4 Visit imageopt
github.com
Spec sheet
- Purpose
- imageopt is a cross-platform command-line image optimizer for local use and CI automation.Read 9 Oct 2026 · github.com
- Free plan
- YesRead 24 Sep 2026 · github.com
- Action platforms
- The composite action supports Linux, macOS, and Windows, and downloads a release binary with SHA-256 verification.Read 9 Oct 2026 · github.com
- API access
- NoRead 24 Sep 2026 · github.com
- Batch processing
- YesRead 24 Sep 2026 · github.com
- CLI features
- The CLI supports dry runs, backups, recursive paths, JSON reports, and a check mode that exits with an error if images could be optimized or a file fails.Read 9 Oct 2026 · github.com
- Compression
- Optimization is lossless by default, with lossy recompression available as an option.Read 9 Oct 2026 · github.com
- Compression modes
- bothRead 24 Sep 2026 · github.com
- Downloads
- Prebuilt binaries are listed for macOS arm64/x64, Linux x64/arm64, and Windows x64.Read 9 Oct 2026 · github.com
- Formats
- It optimizes JPEG, PNG, WebP, SVG, and static GIF files; animated GIF and animated WebP are skipped.Read 9 Oct 2026 · github.com
- GitHub Actions
- A composite GitHub Action can optimize files, commit results, or gate a pull request when images could shrink.Read 9 Oct 2026 · github.com
- Image resizing
- NoRead 24 Sep 2026 · github.com
- Installation
- Users can download a platform binary or install from source with Cargo; building requires Rust 1.82, a C compiler, nasm, and cmake.Read 9 Oct 2026 · github.com
- License and pricing
- The software is licensed GPL-3.0-or-later; the opened project pages state no price.Read 9 Oct 2026 · github.com
- Metadata controls
- YesRead 24 Sep 2026 · github.com
- Notable limits
- AVIF is detected and skipped, and animated GIF and animated WebP are not optimized.Read 9 Oct 2026 · github.com
- Safety
- The engine re-decodes candidate outputs, selects the smallest valid result, and writes files atomically.Read 9 Oct 2026 · github.com
- Security and reliability
- The project says it guards against decompression bombs and leaves failed files untouched.Read 9 Oct 2026 · github.com
- Supported formats
- JPEG,PNG,WebP,SVG,static GIFRead 24 Sep 2026 · github.com
Plans and prices
imageopt Free GPL-3.0-or-later · CLI and GitHub Action · no paid plans or usage limits stated Read 9 Oct 2026 · github.com
Where Specifiction places it
- Image Compression Software#34 of 858.1
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