XeroWP
UWH Image Optimizer & Converter

UWH Image Optimizer & Converter

5/5 (1 ratings) 100 active installs Updated Oct 31, 2026
AVIFimage compressionimage converterimage optimizationwebp
Download v3.4.2 Plugin Website

Optimize and convert WordPress images to WebP, AVIF, JPEG or PNG, review images used by a specific page, and manage Media Library bulk optimization with previews and rollback controls.

UWH Image Optimizer & Converter processes images locally using compatible GD, Imagick or ImageMagick capabilities on your hosting server. No third-party conversion account or cloud API is required. Available output formats depend on your server’s encoders.

WordPress image compression and conversion

  • Convert supported images into WebP, AVIF, JPEG or PNG with adjustable quality and maximum dimensions.
  • Protect originals with a configurable minimum-savings requirement and optional retained backups.
  • Skip animated GIFs to preserve animation; check source MIME, size, dimensions and memory requirements.
  • Use single-image or bulk Media Library optimization with progress, pause, resume and cancellation.
  • Compare before and after in a non-destructive preview, or run an analysis without changing files.

Optimize images by page or post

  • Find local Media Library images referenced by Gutenberg blocks, Elementor content, featured images and common image URLs.
  • Use the Page Image Action Planner to prioritize large source images and review image dimensions and Media Library alt text.
  • Select which images to optimize without changing every image on the page automatically.
  • See remote image references without downloading or modifying them.

Restore and manage images

  • Maintain up to three saved rollback snapshots per attachment when storage is available.
  • Inspect local conversion history, reported savings and restoration availability.
  • Choose image output format, quality and dimensions per run without replacing your global settings.
  • Keep existing attachment GUID values unchanged.
  • Use the Universal Converter to add a converted image to the Media Library.

Important: Changing a Media Library image can affect every page using that attachment. Make a site backup before bulk processing. The Action Planner assesses stored source files, not measured website speed, LCP or Core Web Vitals. Empty Media Library alt text is a review prompt; decorative images may intentionally have an empty alt attribute.

Privacy

The plugin does not send image files, analytics, conversion results, or dashboard activity to United Web Host or another third party.

Browser conversion code is loaded from readable files bundled with this plugin, including assets/js/uwh-image-toolkit.js. The UWH HEIC/HEIF native-browser bridge is available as readable source at assets/js/uwh-browser-heif-decoder.js. It is not the third-party heic2any library.

External services: none are required or contacted by the plugin for image conversion. If your hosting environment provides PHP Imagick, GD, or an ImageMagick command-line binary, those local server components may be used to perform conversion.

No tracking cookies are created by this plugin.

  • Universal Converter staging is isolated from automatic WordPress upload conversion to avoid redundant processing when both features are enabled.
  • File identification uses matching server and browser binary-signature policies, including strict ISO-BMFF brand parsing rather than arbitrary string matches.

Readable Source and Build Information

All production JavaScript and CSS in this plugin is distributed as human-readable, directly editable source. No bundler, transpiler, external JavaScript service, minified vendor package, or build command is required: edit the files below directly and package this plugin folder as a ZIP.

  • Dashboard JavaScript: assets/js/uwh-admin-dashboard.js (source and runtime file are the same).
  • Universal Converter and uploader scripts: assets/js/universal-converter.js, assets/js/upload-preconverter.js.
  • Shared modules: assets/js/uwh-image-toolkit.js, assets/js/uwh-conversion-transport.js and assets/js/uwh-browser-heif-decoder.js.
  • Dashboard CSS: assets/css/uwh-admin-dashboard.css.
  • Legacy converter screen CSS: assets/css/uwh-universal-converter.css.

These are the editable files distributed with the GPL-2.0-or-later project. WordPress and any locally installed PHP GD, Imagick or ImageMagick libraries remain dependencies provided by the site’s environment. There are no bundled third-party JavaScript libraries in the ZIP. The HEIF browser bridge is not a bundled HEIC decoder; native browser support or a compatible server encoder is still required.