Short answer
Mostly, but not uniformly. Safari and Chromium-based browsers treat CSS colours and untagged images as sRGB and convert them for the display; Firefox by default converts images that carry a profile but its long-running work to manage untagged content and CSS colours by default had not landed on the review date. Operating systems differ too: Apple platforms manage colour system-wide, while Windows does so automatically only in HDR mode or on SDR displays provisioned for it. Games, web views, older desktop apps and some image pipelines remain the weak points.
A colour-managed application knows two things: the colour space its content is in (from an embedded ICC profile, a colour tag, or a default of sRGB) and the colour space of the display (from the operating system's display profile). It converts from one to the other, so a given colour looks the same on any display that can produce it. An unmanaged application skips the conversion and sends its numbers straight to the panel. On a display whose primaries are close to sRGB the difference is small; on a wide-gamut display it is obvious, because every sRGB colour is stretched to the panel's more saturated primaries.
CSS says that legacy colours and untagged images are sRGB. WebKit has colour-matched all images on macOS and iOS, treating untagged ones as sRGB, since at least 2016. Chromium announced in 2017 that it would stop stretching untagged images to the monitor's gamut and would convert them, and CSS colours, from sRGB for whichever monitor they are on. Firefox has long converted images that embed a profile, but its tracking bug for converting untagged images and CSS colours by default was still open when Colourwise checked: a 2020 attempt was backed out. Firefox users on wide-gamut screens may therefore see CSS colours and untagged images more saturated than in other browsers, depending on platform and settings. This is the part of this page most likely to change; check current behaviour before relying on it.
A browser can only convert to the profile the operating system reports. Apple's platforms colour-manage the whole desktop, and their built-in displays ship with profiles. Windows historically left colour management to applications and assumed sRGB everywhere; Microsoft's documentation describes automatic system colour management arriving for HDR displays in Windows 10 and extending to SDR displays in Windows 11 version 22H2 — but only for displays provisioned by the manufacturer or a calibration tool with a suitable profile, and with out-of-gamut colours clipped. On Linux the situation depends on the desktop environment and compositor. A wrong or generic display profile makes a managed app convert accurately to the wrong target, which can look worse than no management at all.
The common failures are at boundaries. Embedded web views inside apps sometimes lack the host browser's colour handling. Games and video players may render straight to the panel. Image-processing services strip profiles to save bytes, turning Display P3 or Adobe RGB images into mis-labelled sRGB. Screenshots may be tagged with the display's profile, so an app that ignores tags shows them wrong. Canvas and WebGL content has its own colour-space settings. Diagnosing any mismatch starts by finding which link in the chain — file, app, operating system or display profile — is not doing what the others assume.
| Component | Untagged images and CSS colours | Tagged images | Certainty |
|---|---|---|---|
| WebKit (Safari) | Treated as sRGB, converted for display | Converted | Documented by WebKit (2016) |
| Chromium (Chrome, Edge, others) | Treated as sRGB, converted for display | Converted for the monitor shown on | Documented intent (2017); Linux details less certain |
| Firefox | Not converted by default on the review date | Converted | Open tracking bug; varies by platform |
| Windows, HDR mode | System converts all apps | App-dependent | Documented by Microsoft |
| Windows, SDR display | System converts only on provisioned displays (22H2+) | App-dependent | Documented by Microsoft |
Why: One browser is not converting sRGB content to the wide-gamut display profile.
Fix: Test with a tagged and an untagged reference image; if only the untagged one differs, the browser's default handling is the cause, not your CSS.
Why: The profile is corrupt, generic, or made for a different display mode.
Fix: Revert to the manufacturer's profile, then re-profile in the display mode you actually use.
Why: The screenshot was tagged with the display profile and the recipient's software ignored the tag.
Fix: Convert screenshots to sRGB before sharing, or use a capture tool that does.
Each statement is labelled by kind — established fact, a standard’s requirement, observed market data, a convention, or Colourwise’s own interpretation or analysis — with the strength of the evidence behind it.
FactModerate evidence
WebKit colour-matches images on iOS and macOS and treats images without an embedded profile as sRGB, so they match CSS colours.
Caveat: Stated in 2016; still consistent with CSS Color 4's requirement that untagged images are sRGB.
Source: Improving Color on the Web (WebKit blog, 1 July 2016)
FactModerate evidence
In 2017 Chromium announced that untagged images would be treated as sRGB and converted for the monitor they are displayed on, making CSS colours match colour-tagged images.
Source: Intent to implement: Color correct rendering (blink-dev, 14 April 2017)
FactModerate evidence
Firefox's bug to enable full colour management (including untagged content) by default was still open on 29 September 2026; an attempt in 2020 was backed out.
Caveat: Actual behaviour can differ by platform and version, and a bug's status can change at any time. Check the current release before relying on this.
Source: Mozilla bug 455077: Enable full color management by default (gfx.color_management.mode = 1)
FactStrong evidence
Windows provides automatic system colour management for HDR displays and, from Windows 11 version 22H2, for SDR displays that have been provisioned with an appropriate ICC profile; otherwise applications must manage colour themselves.
Source: Use DirectX with Advanced Color on high/standard dynamic range displays
Reviewed 29 September 2026. Colourwise summarises its sources in its own words and does not reproduce standards text or proprietary colour data. Spotted an error? Tell us.