Chrome network error · -312 · HTTP

ERR_UNSAFE_PORT

Attempting to load an URL with an unsafe port number. These are port numbers that correspond to services, which are not robust to spurious input that may be constructed as a result of an allowed web construct (e.g., HTTP looks a lot like SMTP, so form submission to port 25 is denied).

Chromium's description

Attempting to load an URL with an unsafe port number. These are port numbers that correspond to services, which are not robust to spurious input that may be constructed as a result of an allowed web construct (e.g., HTTP looks a lot like SMTP, so form submission to port 25 is denied).

Chrome shows it as net::ERR_UNSAFE_PORT, error -312. puppeteer and Playwright report the same name when a page fails to load in Chromium.

ERR_UNSAFE_PORT in the screenshot API

When the page itself fails to load with ERR_UNSAFE_PORT, the API answers 502 with the message The target website could not be loaded (ERR_UNSAFE_PORT). (target_unreachable). Not billed.

Only the page's own load can fail a render. An image, script or frame of the page that fails with a network error does not: the page is captured as the browser shows it without that resource.

Check whether a website loads

Device

Format

Full page Block ads

Rendered in a real browser with cookie banners hidden. Takes 5–30 seconds.

Other common errors

ERR_CONNECTION_RESET ERR_CONNECTION_REFUSED ERR_CONNECTION_TIMED_OUT ERR_CACHE_MISS ERR_ADDRESS_UNREACHABLE ERR_TIMED_OUT ERR_SSL_PROTOCOL_ERROR ERR_CONNECTION_CLOSED ERR_QUIC_PROTOCOL_ERROR ERR_NAME_NOT_RESOLVED ERR_TOO_MANY_REDIRECTS ERR_NETWORK_CHANGED

All 249 Chrome network errors · Screenshot API errors

Screenshot API

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Website screenshot Capture any page as an image. Full page screenshot Capture a whole page, top to bottom. Mobile website screenshot See a site on iPhone, Android and iPad. URL to PDF Save any web page as a PDF. URL to markdown Turn a web page into markdown. HTML to PDF Print your own HTML as a PDF. HTML to image Render HTML and CSS as a PNG, JPG or WebP. HTML to markdown Turn HTML into clean markdown. URL to PNG Save a web page as a PNG image. URL to JPG Save a web page as a JPG image. Scrolling screenshot One long image of a page, no stitching. HTML to PNG Render HTML as a lossless PNG. HTML to JPG Render HTML as a compact JPG. Viewport sizesScreen sizes and pixel ratios of 46 devices. ErrorsChrome network errors and screenshot API errors, with fixes.