One set of hashtags does not work across every platform. Each channel has different norms.
Instagram still supports up to 30 hashtags, but quality beats quantity. Use 10 to 15 well-chosen tags. Mix niche and broad hashtags, and always include a location tag if you serve a local audience.
TikTok works differently. Three to five focused hashtags tend to perform better here. TikTok's algorithm relies less on hashtags and more on content quality, but the right tags still signal relevance to the platform.
LinkedIn works best with three to five professional, industry-specific hashtags. Keep them clean and relevant. Overly trendy or casual hashtags look out of place here.
Facebook hashtags have limited impact. One or two are fine, but don't over-invest your time here.
Build two or three saved hashtag sets for each platform. You can rotate them to avoid appearing repetitive.