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Input
Output (paste into head)
Put the generated tags inside head. If a tag with the same name already exists, remove one of them instead of duplicating. Keep exactly one canonical, one og:url and one og:image per page.
Preview
Search result
Social card
Checks

    How to read it

    Length in full-width units

    This tool counts a half-width character as 0.5 and a full-width character as 1. Whether text is truncated in search results depends on display width, not character count, so counting both as 1 makes a title full of Latin characters look shorter than it is. The guides here are 30 for title and 120 for description. No official limit is published, so treat these as guides, not rules.

    Why relative URLs do not work

    A relative path in canonical or og:image cannot be resolved when a social crawler fetches the page, and you end up with a card with no image. It is easy to miss because it looks correct in your own browser. This tool flags any value that does not start with http:// or https://.

    Tags that must appear once

    canonical, og:url and og:image cannot be duplicated, or search engines and social platforms have no way to pick one. On sites where a template already emits shared tags, adding page-specific ones often produces duplicates. Check the existing head for the same tag names before pasting.

    Frequently asked questions

    How long should the description be?

    There is no fixed limit. The length shown in search results varies by device and query, so this tool treats 120 full-width units as a guide and warns past 140. Put what matters first and it still reads when truncated.

    Can og:image be a relative path?

    No. Social platforms fetch the page from their own servers and cannot resolve relative paths. Use an absolute URL starting with http:// or https://. This tool flags relative paths.

    Can title and og:title be the same?

    Yes. If you want to differentiate, keep title search-oriented with keywords first and make og:title easier to read. This tool emits the same value, so edit the output if you need them to differ.

    Is what I type sent anywhere?

    No. Generating the tags, the previews and the checks all happen inside your browser. Only the image URL is fetched, and that is done directly by your browser for the preview.