WebP Converter Without Upload – 100% Private, Browser-Based
Convert JPG and PNG images to WebP without sending a single file to any server. Processing happens entirely in your browser using the Canvas API. GDPR-safe, free, and works offline after load.
Convert Images to WebPFree · No sign-up · No file upload
Why use Crupper?
Zero File Upload
Unlike TinyPNG, Convertio, or iLoveIMG, Crupper processes images locally in your browser. Nothing is transmitted to any server.
GDPR-Safe by Design
No file transfer means no personal data processing under GDPR. Perfect for EU businesses handling sensitive images.
Works Offline
After the initial page load, conversion works without an internet connection. Your files, your device, your control.
Batch Convert – Up to 50 Files
Convert an entire folder of images at once and download as ZIP. All processing stays on your device.
Crop & Resize Included
Built-in crop and resize tools. Edit your images before conversion – all without any server interaction.
Free, No Sign-Up
Core conversion features are free with no account required. Paid plans unlock higher batch limits.
How it works
- 1
Select your images
Drag and drop JPG or PNG files into the converter. Files are read locally – no upload happens.
- 2
Optionally edit
Use the built-in crop or resize editor to adjust images before conversion.
- 3
Convert in your browser
Click Convert. Your browser's Canvas API processes the images locally on your device.
- 4
Download WebP files
Download individual files or grab everything as a ZIP. Your originals are never modified.
Frequently asked questions
- How does a WebP converter without upload work?
- Crupper uses the browser's Canvas API to process images directly in your browser tab. When you select a file, it is read into memory locally and converted to WebP using your device's CPU – no internet connection to a server is needed for the conversion itself.
- Is this really GDPR-compliant?
- Yes. Since no files leave your browser, there is no data transfer to process under GDPR. Your images are never stored, processed, or accessible by Crupper's servers. This makes it ideal for sensitive documents, medical images, personal photos, and confidential business materials.
- How is this different from TinyPNG, Convertio, or Squoosh?
- Most online converters (TinyPNG, Convertio, iLoveIMG) upload your files to their servers for processing. Squoosh also processes in-browser but only handles one image at a time and lacks batch processing. Crupper combines browser-based processing with batch convert (up to 50 files), crop, resize, and quality control – all without any file upload.
- Does it work offline?
- After the initial page load, image conversion works without an active internet connection. This makes Crupper useful in environments with restricted connectivity.
- What image formats are supported?
- Crupper converts JPG, JPEG, and PNG images to WebP format. Support for AVIF is coming soon.
- Can I convert sensitive or confidential images?
- Absolutely. Since files never leave your device, Crupper is safe for medical images, legal documents, financial records, personal photos, and confidential business assets.