ShortPixel plugin review and common issues

Each image thumbnail generated by WordPress consumes a separate credit. A single uploaded image with 5 registered thumbnail sizes uses 5 credits. If WebP or AVIF conversion is enabled, each size generates an additional converted version — doubling or tripling credit consumption per upload. To reduce credit usage: go to ShortPixel → Settings → Advanced and disable AVIF if not needed; reduce the number of WordPress-generated thumbnail sizes by cleaning up unused sizes via a plugin like Regenerate Thumbnails. Check the ShortPixel dashboard for a detailed breakdown of credit consumption.

Once credits are exhausted, ShortPixel queues images but does not process them. Purchase additional credits in the ShortPixel dashboard (accessible from your WordPress admin via ShortPixel → Your Account). After adding credits, go to ShortPixel → Bulk SmushPixel and restart the bulk optimization — previously queued images will process using the new credits. Monthly plan subscribers have their credits refreshed automatically at the billing cycle.

ShortPixel backs up original images before processing (if backup is enabled in settings). Go to ShortPixel → Settings and confirm backup is enabled. To restore specific images, go to the media library, open the attachment details, and click Restore Original in the ShortPixel panel. To restore all images, use the Bulk SmushPixel tool with “Restore all” option. After restoring, switch from Lossy to Glossy or Lossless compression and re-process for a better quality/size balance.

Go to ShortPixel → Other Media → Custom Folders. Add the absolute server path to any folder you want to optimize — for example, /wp-content/themes/your-theme/images/ or /wp-content/plugins/your-plugin/assets/. ShortPixel will scan and optimize images in these folders alongside the media library. This is particularly useful for theme and plugin image assets that are not uploaded through the media library but still affect page load size.

Yes. In ShortPixel → Settings → Advanced, enable WebP Conversion and/or AVIF Conversion. ShortPixel creates WebP/AVIF versions of each image alongside the originals. For WordPress to serve these versions, configure your server to deliver WebP/AVIF to supporting browsers — ShortPixel provides .htaccess snippet instructions for Apache. On Nginx, add server-level rules to check for WebP file existence and serve it. Alternatively, ShortPixel’s CDN option handles format negotiation automatically.

ShortPixel uses one-time credits (or monthly subscription) that roll over — unused credits are not lost at month-end with a one-time purchase. Imagify uses a monthly quota that resets regardless of usage. For sites with seasonal traffic patterns or irregular upload schedules, ShortPixel’s one-time credits are more economical — you pay for what you use. Imagify’s monthly subscription is simpler if your upload volume is consistent.

Yes — ShortPixel supports AVIF conversion, which is the next-generation format beyond WebP. AVIF typically achieves 20–30% smaller file sizes than WebP at equivalent quality. ShortPixel is one of the few WordPress optimization plugins with AVIF support. Browser support for AVIF continues to expand — as of 2025, Chrome, Firefox, Safari, and Edge all support AVIF. Enable it in ShortPixel settings for maximum compression on modern browsers.

Yes, that can happen, especially on older sites with many plugins. This usually happens when the plugin, theme, and add-ons are updated out of sequence. In most cases, testing on staging catches the issue before it reaches the live site. From experience, backups and changelog reviews save a lot of cleanup time.

Start by checking whether another plugin already does the same job. In most cases, overlap is what creates avoidable conflicts and performance issues. A common issue is installing a plugin because it looks convenient without checking the stack first. From experience, a short compatibility review avoids most of the pain later.