microsoft/playwright · error · Error

Device descriptor not found: '${options.device}', available

Error message

Device descriptor not found: '${options.device}', available devices are:

What it means

Thrown by validateOptions when `--device` names a key not present in `playwright.devices`. The error message lists all available device descriptors to help correction. The check is `options.device && !(options.device in playwright.devices)`.

Source

Thrown at packages/playwright-core/src/cli/browserActions.ts:365

  switch (name) {
    case 'chromium': browserType = playwright.chromium; break;
    case 'webkit': browserType = playwright.webkit; break;
    case 'firefox': browserType = playwright.firefox; break;
    case 'cr': browserType = playwright.chromium; break;
    case 'wk': browserType = playwright.webkit; break;
    case 'ff': browserType = playwright.firefox; break;
  }
  if (browserType)
    return browserType;
  program.help();
}

function validateOptions(options: Options) {
  if (options.device && !(options.device in playwright.devices)) {
    const lines = [`Device descriptor not found: '${options.device}', available devices are:`];
    for (const name in playwright.devices)
      lines.push(`  "${name}"`);
    throw new Error(lines.join('\n'));
  }
  if (options.colorScheme && !['light', 'dark'].includes(options.colorScheme))
    throw new Error('Invalid color scheme, should be one of "light", "dark"');
}

View on GitHub (pinned to c8fc3bf8d3)

Solutions

1. Read the error output: it enumerates every valid descriptor name.
2. Copy the exact descriptor string (including spacing/capitalization) from the list.
3. Upgrade Playwright if you need a device added in a newer release.

Example fix

# before
npx playwright open --device='Pixel 7' https://example.com  # not a real descriptor

# after
npx playwright open --device='Pixel 5' https://example.com  # use a listed name

import devices from 'playwright-core/devices';
function assertDeviceKnown(name?: string) {
  if (name && !(name in devices))
    throw new Error(`Unknown device '${name}'. Valid: ${Object.keys(devices).slice(0, 10).join(', ')}...`);
}

import devices from 'playwright-core/devices';
function isKnownDevice(name: string): boolean {
  return name in devices;
}

try {
  validateOptions(options);
} catch (e) {
  if (/Device descriptor not found/.test(e.message)) {
    const suggest = closestMatch(options.device, Object.keys(devices));
    throw new Error(`Unknown device '${options.device}'. Did you mean '${suggest}'?`);
  }
  throw e;
}

When it happens

Trigger: Running `playwright open --device=PixelX` (typo or non-existent descriptor) or any CLI command consuming `--device`. The descriptor name must exactly match a key exported by `DeviceDescriptors`.

Common situations: Typo in the device name; using a marketing name instead of the descriptor key; outdated Playwright version lacking a newer device; case mismatch.

Related errors

• Invalid viewport size format: use "width,height", for exampl
• Invalid geolocation format, should be "lat,long". For exampl
• Error while parsing selector `${selector}` - selector cannot
• PDF creation is only working with Chromium
• Invalid color scheme, should be one of "light", "dark"

AI-assisted analysis of microsoft/playwright@c8fc3bf8d3 (2026-08-12). Data as JSON: /api/errors/c10c8c3273fd23f9. Report an issue: GitHub.