| Component name | color_depth |
|---|---|
| In the visitorId | yes |
| structuredId group | device (screen, memory, CPU) |
| Hashing | plain value; a digest only when longer than 128 characters or not printable ASCII |
| Excluded under | no browser class |
| Inner timeout | 1000 ms |
| Added in | signalsVersion 1 |
Colour depth is how many bits the screen uses to describe the colour of one pixel. Almost every screen says 24; some wide-colour and HDR setups say 30. It separates only a few groups of devices on its own, but it costs nothing to read and adds to the device picture.
What it reads
screen.colorDepth, reported as a whole number in plain text.
How the technique works
The value comes straight from the browser’s screen object, which reflects the display and the operating system’s colour settings. If it is not a finite number, the component is unavailable / no_api.
Why it helps
Few distinct values exist, so the signal is weak alone. It helps in combination: a 30-bit screen narrows the device group, and it moves with display changes that other device components may not see. It is in the device group of the structuredId. On your server it is also a cheap consistency check: a phone user agent with a 30-bit colour depth, or a value that changes between two requests in the same session, is worth a look together with the other screen values.
Stability
Very stable. It changes when the window moves to a display with a different colour depth, when HDR or the display’s colour mode is switched in the operating system, or on a different device.
Browser support and what blocks it
ok in all browsers; not in the exclusion table. The container test runs used for these pages reported 24 in headless Chromium, Firefox and WebKit. The same value is compared with a clean iframe by iframe_mismatch, and its getter is checked by native_tampering.
Because most displays report 24, expect the same value on most of your traffic; the component then adds little on its own, and its main use is the combination with the other device and prefs values.
Privacy
A single coarse number, read without permission or prompt. WhiskerJS sends nothing itself.
How WhiskerJS handles noise and failures
| Status | ruleId | When |
|---|---|---|
ok |
none | for example 24 |
unavailable |
no_api |
no screen or no numeric colorDepth |
blocked |
security_error, threw |
reading threw |
excluded |
caller_excluded |
your exclude list |
timed_out |
timeout, aborted |
1000 ms inner timeout, budget, abort |
Example value
"color_depth": { "status": "ok", "value": "24", "hashed": false }Questions and answers
What values does color_depth usually have?
Most screens report 24. Some wide-colour or high dynamic range setups report 30. Other values are rare.
Is color_depth the same as color_gamut?
No. color_depth is the number of bits per pixel the screen reports; color_gamut is the colour space the display covers (srgb, p3 or rec2020), read with a media query.