[Launch options](https://cdpfleet.com/docs/options)

# `os`

Operating system of the generated fingerprint.

**Use it for:** Matching the persona to who a site expects (a Windows desktop for most consumer sites, macOS for design or creative tools), and keeping one account on the same OS every time.

**Browsers:** [Camoufox](https://cdpfleet.com/docs/browsers/camoufox#opt-os).

## Details

-   **Type:** `"windows" | "macos" | "linux" | array`
-   **Default:** random among windows / macos / linux
-   **Example:** `{"os":"windows"}`

The OS the spoofed fingerprint claims to run on. A list picks one at random per session.

Required when `webgl_config` is set. Any other value returns 400.

## Used in

-   [Case 52: Installed fonts as a fingerprint: what a width probe sees on each Camoufox persona](https://cdpfleet.com/docs/cases/fonts-fingerprint)
-   [Case 49: The same Camoufox device across relaunches: what a persistent profile keeps, and what it doesn't](https://cdpfleet.com/docs/cases/camoufox-same-device)
-   [Case 16: What headless gives away, what headful fixes, and what neither does](https://cdpfleet.com/docs/cases/headless-tells)
-   [Case 15: Three countries, one script — and reading values the way the site does](https://cdpfleet.com/docs/cases/three-countries)
-   [Case 4: A German Windows persona with Camoufox — and the one setting that broke it](https://cdpfleet.com/docs/cases/camoufox-persona)
-   [Camoufox with a Windows fingerprint](https://cdpfleet.com/docs/examples#camoufox-fingerprint)
-   [Camoufox: pinned version, macOS persona, no images](https://cdpfleet.com/docs/examples#camoufox-lean-persona)
-   [Camoufox with a fixed screen and window](https://cdpfleet.com/docs/examples#camoufox-fixed-screen)
-   [Camoufox as a Windows laptop with Intel graphics](https://cdpfleet.com/docs/examples#camoufox-intel-laptop)
-   [Camoufox with exact fingerprint values](https://cdpfleet.com/docs/examples#camoufox-config)
-   [Camoufox reporting an older Firefox](https://cdpfleet.com/docs/examples#camoufox-ff-version)
-   [Camoufox with a macOS font list](https://cdpfleet.com/docs/examples#camoufox-mac-fonts)
-   [Camoufox that keeps the same device and login](https://cdpfleet.com/docs/examples#camoufox-profile)
-   [cdpfleet residential from Windows devices, with a matching persona](https://cdpfleet.com/docs/examples#resi-os-persona)

All options: [launch options](https://cdpfleet.com/docs/options).

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Source: https://cdpfleet.com/docs/options/os · Markdown: https://cdpfleet.com/docs/options/os.md · All docs for AI tools: https://cdpfleet.com/llms.txt