WebP to HDR Converter
Convert WebP to HDR in your browser. WebP files usually come from websites, Chrome's Save image as, CDNs and Android apps; HDR is the better fit for 3D lighting and environment maps. You get a Radiance RGBE (.hdr) file, with the 8-bit sRGB values converted to linear light. Nothing is uploaded.
- Processed locally
- No upload, no wait
- No sign-up
- No watermark
Drop images here
or choose files · paste with Ctrl/⌘ V
WebP expected · other image formats also work
How to use WebP to HDR
- 1
Add your WebP files: drop them here, choose them, or paste from the clipboard.
- 2
Pick the colour that replaces transparent areas, since HDR has none.
- 3
Click Convert. Each file is decoded and encoded in a background thread on this device.
- 4
Download the .hdr files one at a time or together as a ZIP.
Why use Aback Images for webp to hdr
Where the HDR goes next
HDR opens in Blender, Photoshop, Houdini, Unreal Engine, Unity and Affinity Photo.
HDR next to WebP
The HDR keeps the decoded pixels without lossy compression, so expect it to be larger than the WebP.
No new artefacts
WebP is already lossy, since it stores lossy VP8 coding or lossless VP8L; the HDR keeps the decoded pixels losslessly, so this step adds no compression damage of its own.
Processed on your device
Your images are decoded, edited and encoded inside this browser tab by Web Workers. Nothing is uploaded to a server.
WebP vs HDR
What changes from WebP to HDR
Encoding: the WebP uses lossy VP8 coding or lossless VP8L; HDR uses run-length encoded RGBE scanlines, and the download is a Radiance RGBE (.hdr) file, with the 8-bit sRGB values converted to linear light.
Bit depth: 8 bits per channel in the WebP; HDR allows an 8-bit mantissa per channel sharing an 8-bit exponent (RGBE), 32 bits per pixel, and the HDR written here has RGBE, 32 bits per pixel.
Colour: RGB; lossy WebP stores colour at half resolution (4:2:0) in the WebP; HDR supports linear RGB (or XYZ in the XYZE variant), written here as linear-light RGB.
Transparency: the WebP stores it as a separate alpha plane, available in lossy as well as lossless files; the HDR has none, so transparent areas are filled with the colour you choose.
Animation: ANMF frame chunks, each with its own delay and blending; the HDR holds one image, so only the first frame is converted.
Metadata: the WebP can carry EXIF, XMP and ICC chunks; HDR can carry a text header with FORMAT, EXPOSURE and optional comments, but nothing is copied across.
About WebP
WebP is Google's web image format. It supports lossy and lossless compression, transparency and animation, and is typically 25 to 35 percent smaller than JPEG at the same visual quality.
A WebP is a RIFF file: 'RIFF', a length, 'WEBP', then chunks. A simple lossy file is one VP8 chunk and a lossless one is VP8L; the extended VP8X header announces alpha, animation, ICC, EXIF or XMP chunks.
WebP files usually come from websites, Chrome's Save image as, CDNs and Android apps.
About HDR
Radiance .hdr stores high dynamic range light values, widely used for 3D environment maps and HDRI lighting.
A Radiance file starts with '#?RADIANCE' (or '#?RGBE'), text lines such as FORMAT=32-bit_rle_rgbe and EXPOSURE, a blank line, a resolution line like '-Y 2048 +X 4096', then the scanlines.
When converting WebP to HDR makes sense
HDR is the better choice for 3D lighting and environment maps, while WebP suits images on websites and in apps.
HDR strengths: True high dynamic range; Standard for HDRI environment maps. Drawbacks to weigh: Needs tone mapping to view on normal screens.
Limitations
- WebP images saved from websites are often already resized and compressed for the page, so the result cannot be sharper than that copy.
- No range is added: the HDR holds the 8-bit picture in linear light, and nothing in it is brighter than the original white.
- 3D software treats the file as linear light, so an ordinary photo used as an environment map may need its exposure raised to light a scene well.
More conversions
Related tools
Convert HDR to WebP in your browser, ready for images on websites and in apps. Batch, private, no uploads.
Convert WebP to JPG in your browser, with transparency filled in a colour you pick. Batch, private, no uploads.
Convert WebP to PNG in your browser, ready for screenshots, logos, graphics and anything that needs transparency. Batch, private, no uploads.
Convert WebP to GIF in your browser, with the animation kept frame for frame. Batch, private, no uploads.
Shrink JPG, PNG, WebP, AVIF and GIF files with MozJPEG, OxiPNG and modern codecs, with a live before/after preview.
Resize to exact pixels, a percentage or a longest side, with Lanczos3 and Magic Kernel resampling. Batch ready.
Strip EXIF, GPS, XMP, IPTC and comments losslessly. Pixels are never re-encoded for JPG, PNG and WebP.
Convert between 34 image formats in bulk: HEIC, WebP, AVIF, JPEG XL, PNG, JPG, GIF, TIFF, SVG, ICO, PSD, RAW and more.
Frequently asked questions
Does converting WebP to HDR lose quality?
HDR is written losslessly, so the pixels are stored exactly as decoded. Artefacts already in the WebP stay, but nothing new is lost.
What happens to transparency when converting WebP to HDR?
WebP stores transparency as a separate alpha plane, available in lossy as well as lossless files. HDR has no alpha channel, so transparent pixels are composited onto a solid colour, white unless you pick another. To keep transparency, convert to PNG, WebP or AVIF instead.
Will my animated WebP stay animated?
No. HDR holds a single image, so only the first frame is kept. Convert to animated WebP, APNG or GIF to keep the motion, or export every frame with the GIF Frame Extractor.
Does saving as HDR make a real HDRI?
No. A real HDRI is merged from several exposures. This file holds an 8-bit image in linear light, so 3D software reads it correctly, but it has no more range than the source.
Which apps open HDR files?
Blender, Photoshop, Houdini, Unreal Engine, Unity and Affinity Photo. It does not open in web browsers.
Are my images uploaded anywhere?
No. Processing happens inside your browser with WebAssembly and Web Workers. The site only downloads the app code and codecs; your files never leave your device. You can confirm this with the live upload counter on the tool, or in your browser's network panel.
Can I process many files at once?
Yes. Drop a whole selection or folder. Files are processed in parallel on several worker threads, each result can be downloaded on its own, and everything can be saved as one ZIP.
Is it free? Is there a file limit or watermark?
It is free with no account, no watermark and no daily limit. The only limit is your device's memory: very large images (over roughly 100 megapixels) may be refused to keep the tab from crashing.