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Free Plugin by Core Essentials v1.1.3

WebP Image Converter & Replacer

Convert images to WebP and replace originals—no duplicates. Save storage and speed up your site. Auto-convert on upload & bulk tools (premium).

WebP Image Converter & Replacer

The facts

Rating
3★ from 2
Active installs
100+
Price
Free
Last updated
27 Oct 2025
Added
Jun 2025
Requires WP
5.8
Tested up to
WP 6.8.8
Requires PHP
7.4
Downloads
66,568

Our analysis

AI-assisted

WebP Image Converter & Replacer is a WordPress plugin that converts images in formats such as JPEG, PNG, and static GIF to the WebP format. It replaces the original images only when the WebP version is smaller, ensuring that your media library remains free of duplicates and your site benefits from reduced disk usage and improved performance.

The plugin integrates fully with your database, updating all references to the new WebP images. It operates on the server side using PHP GD or Imagick, without relying on external APIs, which helps maintain privacy. This plugin is suitable for users looking to optimise their site's images for better loading speeds and storage efficiency.

Best for: This plugin is best for WordPress users seeking to optimise image performance and reduce storage usage.

What it does well

  • Converts images to WebP format, reducing file size
  • Replaces originals only if the WebP is smaller
  • No duplicate files in the media library
  • Integrates with the database to update image references
  • Lightweight operation with no front-end impact

Where it falls short

  • Original images may be deleted if not backed up
  • Limited features in the free version compared to premium

Verdict

WebP Image Converter & Replacer provides a straightforward solution for image optimisation, particularly for those prioritising performance and storage efficiency. However, users should ensure they back up their files before using it.

From the developer

Core Essentials's own description of WebP Image Converter & Replacer, lightly tidied.

WebP Image Converter & Replacer converts your images (JPEG, PNG, static GIF) to WebP, replaces originals only when smaller, and updates database references so your site transparently serves .webp. No duplicate files. No front-end bloat. Just faster pages and less disk usage.

Why this plugin
No Duplicate Images: Converts and replaces originals when WebP is smaller, keeping /uploads lean.
Real Performance Gains: WebP typically reduces size ~25–35% at similar quality, aiding Core Web Vitals.
Safety First: Never deletes the original unless conversion succeeds and the WebP is smaller.
Full DB Integration: All generated sizes are converted; URLs in content/meta are updated to .webp.
On-Server Only: Uses PHP GD or Imagick. No external API, keys, or privacy concerns.
Lightweight: Runs only during conversion—nothing extra on the front end.

Free features
– Convert individual images from Media → Library (list view).
Optimization Overview with counts: convertible, converted, remaining, skipped, failed, total space saved.
– Smart memory handling to avoid PHP exhaustion on large images.

Premium features
Auto-convert on upload: New images become WebP automatically.
Bulk convert selected: Multi-select in Media Library (list view).
Bulk convert all: Library-wide conversion with progress + pause/resume.

Whether you’re tight on storage or chasing better performance, this is a safe, effective way to modernize images.

IMPORTANT: Because originals may be deleted, back up your /wp-content/uploads/ and database before converting. Test on staging if possible.

How it works

  1. Plugin checks server support (GD/Imagick with WebP).
  2. You convert images (single/bulk/premium auto).
  3. If the .webp is smaller, the original file is removed and all DB refs switch to .webp.
  4. Your site now serves WebP transparently—no theme changes required.

Usage

Optimization Overview
Settings → Media → “WebP Image Converter & Replacer”
– See totals converted/remaining/skipped/failed and space saved.

Convert individual images
Media → Library (list view) → Convert to WebP link under each item.

Premium
Auto-convert on upload: toggle under Settings → Media.
Bulk convert selected: select items in Media Library (list view) → bulk action Convert to WebP.
Bulk convert all: Start Bulk Optimization with progress + pause/resume.

After conversion
– Verify pages serve .webp in browser dev tools.
– Clear any caches/CDN.

Phoenix Media Rename Integration

We integrate with Phoenix Media Rename to safely update all database references.

Why Phoenix?
– Mature, reliable database URL updates across posts, custom fields, widgets, Customizer, etc.
– Reduces risk vs. “DIY” find/replace logic used by other optimizers.
– Lets this plugin focus on conversion while Phoenix handles DB updates.

Read the full description on the official page →

Tagged as

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