HTMLIFrameElement

<iframe> iframe

Baseline: Widely available on the web, in every major browser since Jul 2015, and long enough to count on (since Jan 2018).

niso: Partial 9.8%. 8 of 81 subtests pass, by system: Linux 9.8%, macOS 9.8%. Engines: QuickJS, the engine niso's WPT run uses; Node and Porffor have no recorded run. WPT results recorded at f3b4fa8, 2026-11-10; web-features 3.45.0. WPT tests · niso's support · HTMLIFrameElement

HTMLIFrameElement is an interface in idl/html.webidl, inheriting HTMLElement, exposed in Window. What it does is on MDN; this page says what niso has of it.

niso has no nested navigables, so an iframe has no content document or window.

Status

The web features its members belong to, each with its Baseline status on the web and how much of the feature’s WPT suite passes in niso (see Web platform support).

Feature	On the web	In niso	Members
<iframe>	Widely available	Partial 9.8% 8 of 81 subtests pass	7
srcdoc	Widely available	Not yet 0 of 29 subtests pass	1
Permissions policy	Limited availability	Not run its tests are not-in-suite	1

Members

constructor

constructor

[HTMLConstructor] constructor();

src

attribute

attribute USVString src;

int32_t niso_htmli_frame_element_get_src(niso_dom* dom, niso_handle self, niso_str* out);
int32_t niso_htmli_frame_element_set_src(niso_dom* dom, niso_handle self, const char* value, size_t value_len);

srcdoc

attribute srcdoc: Not yet

attribute DOMString srcdoc;

int32_t niso_htmli_frame_element_get_srcdoc(niso_dom* dom, niso_handle self, niso_str* out);
int32_t niso_htmli_frame_element_set_srcdoc(niso_dom* dom, niso_handle self, const char* value, size_t value_len);

name

attribute

attribute DOMString name;

int32_t niso_htmli_frame_element_get_name(niso_dom* dom, niso_handle self, niso_str* out);
int32_t niso_htmli_frame_element_set_name(niso_dom* dom, niso_handle self, const char* value, size_t value_len);

allow

attribute Permissions policy: Not run

attribute DOMString allow;

int32_t niso_htmli_frame_element_get_allow(niso_dom* dom, niso_handle self, niso_str* out);
int32_t niso_htmli_frame_element_set_allow(niso_dom* dom, niso_handle self, const char* value, size_t value_len);

width

attribute

attribute DOMString width;

int32_t niso_htmli_frame_element_get_width(niso_dom* dom, niso_handle self, niso_str* out);
int32_t niso_htmli_frame_element_set_width(niso_dom* dom, niso_handle self, const char* value, size_t value_len);

height

attribute

attribute DOMString height;

int32_t niso_htmli_frame_element_get_height(niso_dom* dom, niso_handle self, niso_str* out);
int32_t niso_htmli_frame_element_set_height(niso_dom* dom, niso_handle self, const char* value, size_t value_len);

contentDocument

attribute

readonly attribute Document? contentDocument;

int32_t niso_htmli_frame_element_get_content_document(niso_dom* dom, niso_handle self, niso_handle* out);

contentWindow

attribute

readonly attribute WindowProxy? contentWindow;

int32_t niso_htmli_frame_element_get_content_window(niso_dom* dom, niso_handle self, niso_handle* out);

Not in niso yet

Members the web has, by the BCD keys web-features 3.45.0 lists, that idl/ doesn’t declare. The list is partial: web-features lists only the keys it maps to a feature.

• adAuctionHeaders (Protected audience)
• allowFullscreen (Fullscreen API)
• browsingTopics (Topics)
• credentialless (Credentialless iframes)
• csp (Content Security Policy (CSP))
• featurePolicy (Feature policy)
• getSVGDocument (<iframe>)
• loading (Lazy-loading images and iframes)
• referrerPolicy (Referrer policy)
• sandbox (Sandboxed iframes)
• sharedStorageWritable (Shared storage)