FILE FORMAT GUIDE
WebP Image (.WEBP): Structure & Safe Inspection
A WebP file stores a still or animated image in a RIFF-based container. WebP can use lossy or lossless image data and may include transparency, profiles and metadata.
Check supported header evidence locally. Identification is not file validation or a malware scan.
Analyze a file locallyQuick facts
- Extension
- .webp
- Format
- WebP Image
- Category
- image
- MIME type
- image/webp
- Standard / developer
- Open with
- ImageMagick identify
What is WEBP?
A WebP header combines the RIFF identifier with a WEBP form type. Chunks distinguish VP8, lossless VP8L and extended features; reading only RIFF is not enough to identify WebP.
- Deliver compressed still or animated images, including images with alpha transparency
How to open WEBP
ImageMagick format support can depend on its build and delegates; check the local format list before relying on this workflow.
ImageMagick identifyCommand-line tool
First run magick identify -list format and confirm WEBP read support in this installation. Then run magick identify -verbose -- input.webp to inspect the format and image characteristics without overwriting the source.
Technical details
- Signature
- 52 49 46 46 [4-byte size] 57 45 42 50
- Encoding
- Not applicable
- Container
- RIFF WebP
- Compression
- Lossy VP8 or lossless WebP, depending on the image chunk
Things to check
- The RIFF size field limits the complete WebP file to just under 4 GiB.
Related formats
- Portable Network Graphics
PNG is a lossless chunk-based raster format, while WebP uses a RIFF container with lossy or lossless image chunks.
- JPEG Image
JPEG is a common lossy-image compatibility target; WebP uses a RIFF container and can also store lossless images.
- AV1 Image File Format
AVIF uses ISO Base Media File Format structures and AV1 coding rather than WebP's RIFF-based container.
Sources & review
Fact review: 2026-09-19. Unknown fields are not inferred from the file extension.