IMG Performer or ShortPixel? The comparison for WordPress image optimization
ShortPixel processes images in the cloud with an account and credits. IMG Performer runs locally, with no account, and adds EU AI Act Art. 50 labelling.
ShortPixel and IMG Performer both convert WordPress images to WebP and AVIF. The difference is where and how: ShortPixel uploads every image to its cloud for processing and works with an account and a credit quota. IMG Performer processes every image locally on your own server, with no account and no credits, and adds EU AI Act Art. 50 labelling and BFSG-ready AI alt text. If data protection, local processing and legal compliance come first, IMG Performer is the better fit. If you want to process a very large library through a cloud and get a CDN from one source, ShortPixel remains a solid tool.
The main differences
| IMG Performer | ShortPixel | |
|---|---|---|
| Vendor | Enfants Terribles digital GmbH (Hamburg) | ShortPixel |
| Processing | local, on your own server | cloud – every image is uploaded to ShortPixel |
| Account required | no | yes |
| AI model (alt text) | your choice – Mistral (France) recommended | – |
| Billing | license, no quota | credits – several per image depending on settings (main format, WebP, AVIF, thumbnails) |
| Data protection | no image transfer to third parties; DPA only for the optional alt-text AI | data processing agreement; DPA and sub-processor list available, but cloud processing |
| EU AI Act Art. 50 | yes, already in the free version | no |
| WebP / AVIF | yes (AVIF in Pro) | yes |
| AI alt text | yes (Pro, your own API key, no credit cap) | yes, via a separate credit quota (100/month free, unlimited tier $9.99/month) |
| AI image detection | automatic (C2PA, EXIF, AI-tool signatures) | – |
| Marker in all image sizes | yes – machine-readable marker in every size incl. WebP/AVIF | – |
| Visible label | yes, customizable design (Pro) | – |
| Platforms | WordPress | – |
| Cost | Free · Pro €69/year or €9/month | Free 100 credits/month · from $3.99/month · one-time packs from $19.99 |
Last verified: August 2026. The current vendor pages are authoritative.
Local processing instead of the cloud
ShortPixel is a cloud service: on optimization, every image is sent to ShortPixel’s servers, compressed there and returned. That requires an account and an API key and is, in data-protection terms, processing on behalf of the controller. IMG Performer runs compression, WebP/AVIF conversion and AI image detection directly on the server that runs WordPress. No image leaves the site, and no account is needed.
Licence instead of a credit quota
ShortPixel bills in credits. A single image uses several credits depending on the configuration, because the main format, WebP, AVIF and the thumbnail sizes each count separately. Anyone who exhausts the monthly quota has to buy more or wait. IMG Performer has no quota: WebP conversion in the free version is unlimited, and the Pro licence costs €69 a year regardless of the number of images.
EU AI Act Art. 50 labelling
Article 50 of the EU AI Regulation has applied since 2 August 2026. IMG Performer detects AI-generated images on upload via C2PA metadata, EXIF hints and signatures of known AI tools, keeps the machine-readable marking intact across every image size, and adds a visible label on request. ShortPixel has no feature for this.
AI alt text for accessibility
Both plugins can generate alt text with AI. ShortPixel uses its own separate credit quota for this (100 alt texts a month free, plus a dedicated unlimited tier for $9.99/month). With IMG Performer you store your own API key with a provider of your choice – Mistral (based in France) is recommended. There is no credit system and no cap; you only pay your actual usage with your AI provider. For a comparison with dedicated alt-text specialists, see IMG Performer, AutoAlt.ai or alttext.ai?.
When ShortPixel is the better choice
- You have a very large media library and want to process it through a cloud without loading your server’s CPU.
- You want image optimization and a CDN from one source and are fine with cloud processing.
- You already use ShortPixel across several projects and want to keep your familiar setup.
When IMG Performer fits
- Data protection and local processing come first – no image transfer to third parties, no account.
- You want to cover the EU AI Act Art. 50 labelling obligation at the same time.
- You need BFSG-ready alt text without being tied to a credit quota.
- You want predictable costs: an annual licence instead of a usage-based quota.
Disclaimer
Note: Information on features and prices – including those of IMG Performer – reflects our knowledge at the time of publication and may change. We accept no liability for its accuracy. The current product and pricing pages of the respective providers are authoritative; information on IMG Performer is available at img-performer.enfants.de.
Frequently asked questions
Can I switch from ShortPixel to IMG Performer without re-uploading images?
Yes. IMG Performer works with the existing originals in the media library and creates new WebP/AVIF variants from them locally. Images already optimized by ShortPixel are left untouched.
Do I lose a CDN with IMG Performer?
IMG Performer does not include its own CDN but does not force one either. You can put any CDN in front of it; the optimization itself happens locally beforehand.
Is local processing slower?
Conversion runs in the background and does not affect page delivery. For very large existing libraries the one-time batch run takes longer than through a cloud – after that everything runs automatically on upload.