Blog · Guide · 21 October 2026

Guide: How to watch a reaction video in sync with Crunchyroll

Full anime reactions on YouTube and Patreon often leave the episode out, so you play it yourself. ReactionSync, a Chrome extension, plays the reaction in sync with the episode on your own Crunchyroll account, each in its own tab. No more 3, 2, 1, play: when the reactor pauses to talk, Crunchyroll waits, and if either video buffers, both wait.

What you need

• A computer with Chrome, Edge, Brave or another Chromium browser.
• Your own Crunchyroll account, on a plan without ads (why).
• The reaction, on a site ReactionSync works with, such as YouTube or Patreon (all supported sites).
• ReactionSync, added from the Chrome Web Store and signed in with Google once. Get Started takes about a minute.

Watch with a sync link

A sync link is made once per reaction: someone has already lined the reaction up with the episode, marked where the reactor pauses, where they skip, and where it ends. Creators usually post it with the reaction.

1. Open both videos. Open the reaction where it was posted, such as the creator’s YouTube video or Patreon post, and the episode on your own Crunchyroll, each in its own tab. If the creator’s link opens a ReactionSync page, its Original on Crunchyroll button opens the episode for you. Put the two side by side (drag one tab out into its own window) and press play on both. If either tab was open before you installed ReactionSync, reload it first.
2. Copy the sync link. On the link’s page, click Copy sync link. Do this before you open the extension, because its window closes when you click anywhere else.
3. Pick your two tabs. Click the ReactionSync icon in your toolbar, pick the Crunchyroll tab under 1. Source and the reaction under 2. Reaction, and click Continue.
4. Load the link. Click Load from Link, paste, and click the arrow. Both start together.

From there, pause, seek or rewind either one and the other follows. Watching a whole season? Each episode’s reaction has its own sync link: click End Session in the extension, open the next pair and load the next link.

No sync link for this reaction?

• Ask the reactor to make one. They make it once, and everyone who watches with them can use it.
• Or line it up yourself and share it for the next person. The creators page walks through it, with a video.

If something’s off

• The Crunchyroll tab isn’t in the list. It has to be on the page where the episode is playing, in view and not muted while you set up. More on this.
• They drift apart slowly over a long stretch. The two copies run at slightly different speeds, often 25 against 24 frames a second. Fix it with the speed correction.
• An ad break threw the timing off. Use a Crunchyroll plan without ads. Ads, by service.

Anything else, or it broke for you: write to support@reactionsync.com and say which two sites you were pairing. Karthik, who built ReactionSync, reads every message.