How to Use This Tool
Every YouTube video has one permanent identifier: an eleven-character string that appears in every link shape YouTube has ever used. Extracting it by hand is easy until you meet a Shorts link, a live link, a mobile link with a playlist attached, or a share link that has picked up four tracking parameters on the way. This tool handles all of them and tells you which shape it recognised.
What counts as a valid ID
The ID is exactly eleven characters from the base64url alphabet: letters, digits, hyphen and underscore. That last detail matters more than it looks. A hyphen or underscore inside the ID is completely normal, so naive extraction code that strips punctuation will quietly corrupt about one ID in eight. If you are writing your own parser, that is the bug you will hit.
Bulk extraction
Paste an entire block of text — a description, a chat log, a spreadsheet column — and every ID in it is pulled out at once, de-duplicated, in the order it appeared. This is the fastest way to turn a messy list of shared links into something you can feed to a script or paste into a playlist builder.
Getting other formats back
Once the ID is identified you also get every URL form built back from it: the canonical watch link, the
short youtu.be form, the embed URL, the Shorts URL, the thumbnail addresses and a no-cookie privacy embed.
If a start time was present in your input it is carried through, converted into whichever parameter that
format expects — t for watch links, start for embeds, which is a difference that
trips people up regularly.
A privacy note about share links
Links copied from the YouTube app carry an si parameter. That is a share-attribution token
tied to the account that copied it. It is harmless in a private message and inappropriate in a public post
or a client deliverable, because it links the published URL back to a specific person. Rebuilding the URL
from the ID, as this tool does, removes it cleanly.