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What is the ?si= in YouTube & Spotify links?

Updated July 2026 · 3 min read
Short answer

si is a share identifier — a token stamped onto the link when you hit Share. The video or song plays exactly the same without it. Delete everything from ?si= onward, or let tdy strip it from every link you copy.

What it does

Hit Share on a YouTube video and you get something like:

https://youtu.be/dQw4w9WgXcQ?si=AbCdEf12345
https://youtu.be/dQw4w9WgXcQ

The si token identifies that specific share event — generated in your app, in your session. When someone opens the link, the platform can connect the view back to the share: who shared, from where, and how far the link traveled as it gets forwarded around. Spotify does the same on track and playlist links.

It's analytics about your social graph, not functionality. Strip it and the link behaves identically.

The same trick by other names

ParameterPlatformSafe to delete?
siYouTube, SpotifyYes
?s=20&t=…X / TwitterYes
igshInstagramYes
rdtRedditYes
xmtThreadsYes
v=, t= (timestamp)YouTubeNo — these select the video / start time

The last row is the reason to be careful with "delete everything after the question mark": on youtube.com/watch links, v= is the video itself.

Removing it automatically

Editing links by hand gets old. tdy, a tiny Mac menu-bar app, strips share tokens — si and all its cousins — from every link the moment you copy it, using a curated list so functional parameters like v= and timestamps survive. Full guide to tracking parameters here.

Share the song, not the token.

tdy cleans every link you copy — automatically, on your Mac. Native, one-time purchase, no subscription.

Get tdy for Mac

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