How to Check an Open Graph Preview
By Tools Star Hub Editorial Team · Published
To check a public page’s share tags, enter an absolute http or https URL and press Check preview. Check preview sends the URL off this device to fetch the page. This site requests that page and shows the title, description, image, and Twitter card it finds. The page is not saved here. A private or local address is rejected before the page is read.
The tags live on the public page, so the check has to fetch that page. The browser sends only the URL to this site. The site resolves the host, rejects a private, loopback, link-local, or reserved address, and checks again after each redirect. It reads at most 512 KiB of the decompressed page, then returns the tags. The raw page is not returned and is not saved.
How to check an Open Graph preview
- Enter an absolute http or https URL. A file URL, a URL with a username, and a private address are rejected. http://127.0.0.1/ and the decimal form http://2130706433/ are both rejected before the page is read.
- Press Check preview. Check preview sends the URL off this device to fetch the page. The site requests that public page. The request stops after 8 seconds. A private or non-http address is rejected.
- Read the card. The card shows the title, description, image address, and Twitter card from the fetched page. An empty field reads Not found. The address after redirects is kept when the redirect stays on a public http or https URL.
- Treat a missing picture as a separate problem. A share image may be listed even when the image host blocks the preview picture. The page itself is not saved here.
Example
A public page
https://example.com/ returns the title Example Domain. That page has no description, image, or Twitter card, so those fields read Not found. The URL was sent off this device so the site could fetch the page.
A local address
http://127.0.0.1/ and the decimal form http://2130706433/ both show That address cannot be fetched. Those addresses are rejected before the page is read.
Things to watch
What leaves this device
Check preview sends the URL off this device to fetch the page. This site requests that public page and reads its tags. The raw page is not returned and is not saved. A timeout shows no card, and the page says the preview request timed out.
Writing tags is a different page
Use the Meta Tag Generator when you want to write the tags yourself. This page reads tags that are already on a public URL, and that read happens after the URL is sent off this device.
FAQ
- What does Check preview send off this device?
- The URL. Check preview sends the URL off this device to fetch the page. This site requests that public page and reads its tags. The page is not saved here. A private or non-http address is rejected.
- What does https://example.com/ show?
- The title Example Domain. That page has no description, image, or Twitter card, so those fields read Not found.
- Why do 127.0.0.1 and 2130706433 both fail?
- Both are loopback addresses. A private, loopback, link-local, or reserved address is rejected before the page is read. The message is That address cannot be fetched.
- What comes back after the page is fetched?
- The tags, not the raw page. The site reads at most 512 KiB of the decompressed page and returns the title, description, image, and Twitter card. The page is not saved here.
To fetch a public page’s share tags, use Open Graph Preview. Check preview sends the URL off this device to fetch the page. The page is not saved here.