Enter a URL above and hit Load to preview it in an iframe.
8 device presets · custom sizes · embeddability check
About the iFrame Tester
Load any URL inside an iframe at a chosen viewport size and find out whether the page actually permits embedding. Many sites block framing with the X-Frame-Options header or a Content-Security-Policy frame-ancestors directive, which produces a blank frame with no visible explanation. This tool checks those headers server-side and tells you which one is responsible.
How to use the iFrame Tester
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Enter the URL to test
Paste the full address including the protocol. Recently tested URLs are kept in a local history so you can switch between them quickly.
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Pick a device preset or set a custom size
Choose from eight common phone, tablet and desktop viewports, rotate between portrait and landscape, or type exact pixel dimensions.
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Read the embeddability result
If the frame stays blank, the header check reports whether X-Frame-Options or a CSP frame-ancestors directive is blocking it, and what the header value was.
When to use it
Debugging a blank embed
Find out in seconds whether a widget fails to load because of your code or because the target site refuses to be framed.
Checking responsive behaviour
See how a page reflows across phone, tablet and desktop widths without resizing your own browser window.
Validating a partner integration
Confirm that a page you are about to embed in a portal or documentation site allows framing from external origins.
Frequently asked questions
Why does the preview stay blank?
Almost always because the target site sends X-Frame-Options: DENY/SAMEORIGIN or a CSP frame-ancestors directive that excludes this origin. The embeddability check reports which header is responsible.
Can I bypass X-Frame-Options?
No, and no tool legitimately can. It is a browser-enforced security control that prevents clickjacking. If you own the target site, adjust the header there; otherwise the restriction is intentional.
Does this show exactly what a real phone shows?
It reproduces the viewport dimensions, which covers most responsive layout issues. It does not emulate a mobile rendering engine, touch behaviour or device pixel ratio, so test on real hardware before shipping.
Is the URL I test recorded?
The embeddability check makes a server-side request to read response headers, so the URL is seen by that endpoint. The recent-URL history is stored only in your browser.
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