Do podcast transcripts actually help with Google rankings?

Yes, because the transcript is the only part of an episode a crawler can read. A transcript turns 40 minutes of speech into indexable text that can match a query and supply a snippet. It is also an accessibility requirement, not a bonus: a transcript is the text version of the speech and non-speech audio needed to understand the content, used by people who are deaf or hard of hearing. The same text serves both audiences at once.

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