ons-Policy: execution-while-not-rendered ](/en-US/docs/Web/HTTP/Headers/Permissions-Policy/execution-while-not-rendered) Experimental 
    12. [ Permissions-Policy: execution-while-out-of-viewport ](/en-US/docs/Web/HTTP/Headers/Permissions-Policy/execution-while-out-of-viewport) Experimental 
    13. [ Permissions-Policy: fullscreen ](/en-US/docs/Web/HTTP/Headers/Permissions-Policy/fullscreen)
    14. [ Permissions-Policy: gamepad ](/en-US/docs/Web/HTTP/Headers/Permissions-Policy/gamepad) Experimental 
    15. [ Permissions-Policy: geolocation ](/en-US/docs/Web/HTTP/Headers/Permissions-Policy/geolocation)
    16. [ Permissions-Policy: gyroscope ](/en-US/docs/Web/HTTP/Headers/Permissions-Policy/gyroscope) Experimental 
    17. [ Permissions-Policy: hid ](/en-US/docs/Web/HTTP/Headers/Permissions-Policy/hid) Experimental 
    18. [ Permissions-Policy: identity-credentials-get ](/en-US/docs/Web/HTTP/Headers/Permissions-Policy/identity-credentials-get) Experimental 
    19. [ Permissions-Policy: idle-detection ](/en-US/docs/Web/HTTP/Headers/Permissions-Policy/idle-detection) Experimental 
    20. [ Permissions-Policy: local-fonts ](/en-US/docs/Web/HTTP/Headers/Permissions-Policy/local-fonts) Experimental 
    21. [ Permissions-Policy: magnetometer ](/en-US/docs/Web/HTTP/Headers/Permissions-Policy/magnetometer) Experimental 
    22. [ Permissions-Policy: microphone ](/en-US/docs/Web/HTTP/Headers/Permissions-Policy/microphone)
    23. [ Permissions-Policy: midi ](/en-US/docs/Web/HTTP/Headers/Permissions-Policy/midi) Experimental 
    24. [ Permissions-Policy: otp-credentials ](/en-US/docs/Web/HTTP/Headers/Permissions-Policy/otp-credentials) Experimental 
    25. [ Permissions-Policy: payment ](/en-US/docs/Web/HTTP/Headers/Permissions-Policy/payment) Experimental 
    26. [ Permissions-Policy: picture-in-picture ](/en-US/docs/Web/HTTP/Headers/Permissions-Policy/picture-in-picture) Experimental 
    27. [ Permissions-Policy: publickey-credentials-create ](/en-US/docs/Web/HTTP/Headers/Permissions-Policy/publickey-credentials-create) Experimental 
    28. [ Permissions-Policy: publickey-credentials-get ](/en-US/docs/Web/HTTP/Headers/Permissions-Policy/publickey-credentials-get)
    29. [ Permissions-Policy: screen-wake-lock ](/en-US/docs/Web/HTTP/Headers/Permissions-Policy/screen-wake-lock)
    30. [ Permissions-Policy: serial ](/en-US/docs/Web/HTTP/Headers/Permissions-Policy/serial) Experimental 
    31. [ Permissions-Policy: speaker-selection ](/en-US/docs/Web/HTTP/Headers/Permissions-Policy/speaker-selection) Experimental 
    32. [ Permissions-Policy: storage-access ](/en-US/docs/Web/HTTP/Headers/Permissions-Policy/storage-access) Experimental 
    33. [ Permissions-Policy: usb ](/en-US/docs/Web/HTTP/Headers/Permissions-Policy/usb) Experimental 
    34. [ Permissions-Policy: web-share ](/en-US/docs/Web/HTTP/Headers/Permissions-Policy/web-share)
    35. [ Permissions-Policy: window-management ](/en-US/docs/Web/HTTP/Headers/Permissions-Policy/window-management) Experimental 
    36. [ Permissions-Policy: xr-spatial-tracking ](/en-US/docs/Web/HTTP/Headers/Permissions-Policy/xr-spatial-tracking) Experimental 

##  In this article

  * Syntax 
  * Description 
  * Examples 
  * Browser compatibility 
  * See also 

#  X-DNS-Prefetch-Control

**Non-standard:** This feature is non-standard and is not on a standards
track. Do not use it on production sites facing the Web: it will not work for
every user. There may also be large incompatibilities between implementations
and the behavior may change in the future.

The **` X-DNS-Prefetch-Control ` ** HTTP response header controls DNS
prefetching, a feature by which browsers proactively perform domain name
resolution on both links that the user may choose to follow as well as URLs
for items referenced by the document, including images, CSS, JavaScript, and
so forth.

This prefetching is performed in the background, so that the [ DNS ](/en-
US/docs/Glossary/DNS) is likely to have been resolved by