The direct answer: 5 to 8 focused tags. Your exact topic phrase, a few variants people really search, one or two specific subtopics, your channel name. That is the whole job, and every tag past it makes the set slightly worse, not slightly better.
Here is the anatomy, the limits, and why the stuffed field keeps losing to the short one.
The anatomy of a working set
| Slot | Count | Example for a sourdough video |
|---|---|---|
| Exact phrase | 1 | sourdough for beginners |
| Real variants | 2-3 | sour dough bread, sourdough starter guide |
| Specific subtopics | 1-2 | sourdough proofing, dense sourdough fix |
| Channel name | 1 | your channel, spelled the one true way |
The variants slot is where the field still earns its keep, catching the misspellings and phrasings of your topic, which is why they should come from real search data rather than imagination. The channel-name slot quietly helps your own videos suggest each other.
Why more stops helping
The mechanism is dilution: the field describes what your video is about, and a tight set states it plainly while a stuffed one mumbles thirty half-truths. For a signal that is already minor, mumbling spends its whole value.
The stuffed field also flirts with the one real hazard: tags about topics the video does not cover fall under misleading metadata, where the downside is enforcement, not just wasted characters.
The limits and the myths
The actual constraint is 500 characters across the field, a ceiling generous enough to enable every bad habit. The myths that fill it:
| Myth | Reality |
|---|---|
| More tags, more reach | Dilution after the focused set; the limit is not a goal |
| Competitor names pull their audience | Policy risk for a dead tactic |
| Tag order is critical | Minor at most; exact phrase first is fine convention |
| Tags rescue discovery | Titles, thumbnails and satisfaction decide reach |
| Single-word tags cover more searches | Phrases match how people search; "bread" claims nothing |
The two-minute routine
Generate from your topic with a grounded tool, keep the set that fits the anatomy table, paste, publish. The same routine as the tags-and-hashtags split prescribed: hygiene done properly, then attention returned to the title and thumbnail where reach is actually decided.
And when an old video needs its tags revisited, resist the urge to expand the set; update the variants to how people search the topic now, which is refresh work, not stuffing.
The one-line takeaway: 5 to 8 tags: exact phrase, real variants, a subtopic or two, channel name. The 500-character limit is a ceiling, not a target, and every tag past the focused set mumbles where the short set spoke clearly.