Parameters & flags

Reach for the friendly SDK options first. Drop to raw flags only when you need a surface the options don't cover. Every flag is derived from, and stays consistent with, your seed.

SDK options

The launch() keyword arguments most people use.

Option	Description
`seed`	int. A stable, repeatable device. Omit for a fresh random identity each launch.
`platform`	"windows" \| "macos" \| "linux". The OS persona (also picks a coherent seed range).
`proxy`	Proxy URL or a named pool. Credentials are passed inline to the binary (no CDP auth leak).
`geoip`	bool. Pin WebRTC IP + timezone + geolocation to the proxy exit for one coherent story.
`locale`	Accept-Language + navigator.language(s).
`timezone`	IANA timezone string; overrides the geoip-derived one.
`humanize`	bool. Human-like input timing and motion via real Playwright input (no CDP tricks).
`license_key`	Your Capium license key. Unlocks the always-latest stealth binary.

Identity

One master seed derives a whole coherent device. Everything below stays internally consistent for that seed.

Flag	Description
`--fingerprint=<seed>` sdk: seed=	Master seed for the entire coherent device. off / false / none = passthrough (your real values, no spoofing).
`--fingerprint-platform=<windows\|macos\|linux>` sdk: platform=	Spoofed OS persona. Rewrites navigator.platform, the User-Agent, and the UA-CH platform.
`--fingerprint-platform-version=<v>`	UA-CH platformVersion (e.g. Windows 10.0.0 vs macOS 13.0.0).
`--fingerprint-brand=<name>`	UA-CH brand entry (the browser brand list reported to sites).
`--fingerprint-brand-version=<v>`	UA-CH brand version entry.
`--fingerprint-hardware-concurrency=<n>`	navigator.hardwareConcurrency (reported CPU core count).
`--fingerprint-screen-width=<n>`	screen.width.
`--fingerprint-screen-height=<n>`	screen.height.
`--fingerprint-device-scale-factor=<f>`	devicePixelRatio.
`--fingerprint-storage-quota=<bytes>`	navigator.storage quota estimate.

Rendering & noise

Per-seed, deterministic noise on the graphics surfaces so the same seed always renders the same way, and two seeds never collide.

Flag	Description
`--fingerprint-noise=<true\|false>` sdk: noise=	Deterministic per-seed noise on canvas image data, measureText, and the audio stack. On by default.
`--disable-spoofing=<canvas,font,...>`	Selectively turn off spoofing for named surfaces (comma-separated).
`--fingerprinting-canvas-image-data-noise`	Fine-grained canvas toDataURL / getImageData noise (prefer --fingerprint-noise).
`--fingerprinting-canvas-measuretext-noise`	Fine-grained canvas measureText noise.
`--fingerprinting-client-rects-noise`	Fine-grained getClientRects / getBoundingClientRect noise.

Fonts & voices

OS-specific text and speech surfaces, matched to the persona.

Flag	Description
`--fingerprint-windows-font-metrics`	Measure default text with Windows metrics for a Windows persona. Requires real Windows fonts on the host.
`--fingerprint-sapi-voices=<true\|false>`	Present the Windows SAPI voice list (speechSynthesis) for a Windows persona.

Location, network & content

Align timezone, geolocation and the WebRTC exit IP to one coherent story, then keep pages lean.

Flag	Description
`--timezone=<IANA>` sdk: timezone=	In-browser timezone, e.g. America/New_York.
`--fingerprint-location=<lat,lon>`	Geolocation API coordinates.
`--fingerprint-webrtc-ip=<ip\|auto>` sdk: geoip=True	The IP WebRTC reports. Pin it to your proxy exit. With geoip the SDK does this, and matches timezone + location, automatically.
`--fingerprint-allow-3p-cookies`	Allow third-party cookies (some SSO and embedded-payment flows need them).
`--disable-ads`	Built-in ad/tracker blocker with a login/captcha-safe allowlist. Cuts bandwidth without breaking flows.

Raw flags

Pass any flag through args= for surfaces without a convenience option:

raw_args.py

from capium import launch

browser = launch(
    seed=200123,
    args=[
        "--fingerprint-hardware-concurrency=8",
        "--fingerprint-screen-width=2560",
        "--fingerprint-screen-height=1440",
    ],
)

Command line

The SDK ships a small CLI. python -m capium status prints your license entitlements; python -m capium <url> launches a browser to a URL, configured by environment variables.

cli.sh

# License entitlements (plan, sessions_cap, live_sessions, period_end)
python -m capium status

# Launch a browser to a URL, configured by env vars
SEED=200123 PLATFORM=linux GEOIP=1 HUMANIZE=1 \
  python -m capium https://fingerprint.com/demo/

Env var	Effect
SEED	Identity seed (integer).
PLATFORM	windows \| macos \| linux.
HEADLESS	1 to run headless (headed is default and recommended).
PROXY	Proxy URL or named pool, e.g. dataimpulse.
GEOIP	1 to align timezone/geo/WebRTC to the exit.
PROFILE	Directory for a persistent context.
HUMANIZE	1 to enable human-like input.
CAPIUM_LICENSE_KEY	License key (else ~/.capium/license).

Cookbook

API reference