color and transparency
HDR / High Dynamic Range
HDR images capture far greater brightness ranges than standard images, from deepest shadows to brightest highlights.
What is HDR / High Dynamic Range?
HDR (High Dynamic Range) images capture, store, and display a far greater range of luminosity — from the deepest shadows to the brightest highlights — than standard dynamic range (SDR) imaging can represent. HDR requires a minimum of 10-bit color depth (1,024 shades per channel versus 8-bit's 256) and specialized transfer functions like PQ or HLG to map brightness values to actual light output. For web images in 2026, AVIF is the only widely supported format with full HDR capability, while JPEG and WebP remain limited to 8-bit SDR.
Importance of HDR / High Dynamic Range
Understanding HDR vs SDR images becomes critical when preparing content for HDR-capable displays like Apple XDR monitors or modern smartphones with HDR screens. Without proper HDR support, your images may appear washed out or lose dramatic contrast on capable devices, while over-processed HDR content can look unnatural on standard displays. This knowledge helps you choose the right format and optimize images for your audience's actual viewing environment.
HDR / High Dynamic Range in Practice
A photographer uploading portfolio images faces a choice: save as standard JPEG (8-bit SDR) for universal compatibility, or export as AVIF with 10-bit HDR for viewers with capable displays. The AVIF HDR file might be 2.3MB compared to a 1.8MB JPEG, but delivers significantly better shadow detail and highlight retention on HDR displays. However, since most web traffic still comes from SDR displays, many photographers create dual versions or rely on AVIF's backwards compatibility.
HDR / High Dynamic Range Best Practices
- → Use AVIF format when targeting users with HDR-capable displays like modern iPhones or professional monitors.
- → Test your HDR images on both SDR and HDR displays to ensure acceptable appearance across all environments.
- → Consider file size increases when implementing HDR — 10-bit images are typically 25-40% larger than 8-bit equivalents.
- → Stick with standard JPEG or WebP for general web use until HDR display adoption reaches mainstream levels.
Example of HDR / High Dynamic Range
Related Terms
Frequently Asked Questions
What is HDR in photography?
HDR (High Dynamic Range) in photography refers to images that capture a much wider range of brightness levels than standard photos, from very dark shadows to very bright highlights without losing detail. HDR images require at least 10-bit color depth and special encoding to store this extended brightness information. Most standard JPEG and WebP images are limited to 8-bit SDR (Standard Dynamic Range) and cannot display the full HDR experience.
Which image formats support HDR?
AVIF is the only web image format with full HDR support in 2026, including 10-bit and 12-bit color depth plus specialized transfer functions like PQ and HLG. HEIC supports HDR for camera applications but has inconsistent browser support for HDR rendering. JPEG and WebP are both limited to 8-bit color depth and cannot store or display HDR content.
Do HDR images work on all websites and displays?
HDR images do not work consistently across all websites and displays in 2026. Most web displays are still SDR monitors, and browsers do not reliably render HDR content in all environments. HDR becomes practical mainly for photography showcases, e-commerce sites targeting HDR-capable devices, and platforms explicitly serving users with Apple XDR displays or HDR-certified monitors.