How Optimise in my voice works
What Cohera changes when it writes a caption for each platform, and where its rules come from.
Updated 17 October 2026
Optimise in my voice rewrites your caption for each platform you post to, using your own past posts. It aims for your usual length and paragraphs on that platform, tidies your sentences and keeps your tone. It never invents facts, and your Settings rules, such as no added exclamation marks, always apply.
It also follows each platform's own published guidance on helping people find posts, such as how many hashtags to use and saying plainly what a video is about. This can make your post easier to find in search. It does not promise more reach.
After you press Continue, tap What changed under any platform to see what Cohera did and why, and remove anything you don't want. Choose Use exact caption to post your words as they are.
The rules Cohera follows for each platform
Up to 5 hashtags
- Instagram allows up to 5 hashtags on a post. Source: Instagram Help Centre (opens in a new tab)Last checked 15 October 2026
- Instagram search matches typed words to hashtag words. Source: Meta Transparency Centre (opens in a new tab)Last checked 15 October 2026
- Instagram's caption limit is 2,200 characters. Source: Meta for Developers (opens in a new tab)Last checked 15 October 2026
TikTok
Up to 5 hashtags (Cohera's choice)
- TikTok says captions and descriptions should make clear what the video is about so searchers find it. Source: TikTok (opens in a new tab)Last checked 15 October 2026
- TikTok says long or loosely related hashtag lists can work against you. Source: TikTok (opens in a new tab)Last checked 15 October 2026
- TikTok can flag stuffed or unrelated text as spam. Source: TikTok (opens in a new tab)Last checked 15 October 2026
- TikTok's caption limit is 2,200 characters. Source: TikTok for Developers (opens in a new tab)Last checked 15 October 2026
YouTube
Up to 3 hashtags
- Only three hashtags show by the title. Source: YouTube Help (opens in a new tab)Last checked 15 October 2026
- Unrelated hashtags can get the video removed. Source: YouTube Help (opens in a new tab)Last checked 15 October 2026
- Viewers may see only part of the title; the limit is 100 characters. Source: YouTube Help (opens in a new tab)Last checked 15 October 2026
- YouTube suggests putting the main words in the first lines, which show before "Show more". Source: YouTube Help (opens in a new tab)Last checked 15 October 2026
- YouTube's description limit is 5,000 characters. Source: YouTube Help (opens in a new tab)Last checked 15 October 2026
- YouTube's spam policy bans misleading words and repeated tag-like sentences. Source: YouTube Help (opens in a new tab)Last checked 15 October 2026
- YouTube says tags barely matter and excessive tags are spam. Source: YouTube Help (opens in a new tab)Last checked 15 October 2026
Up to 3 hashtags (Cohera's choice)
- Facebook turns valid hashtags into searchable links; spaces and symbols break them. Source: Facebook Help Centre (opens in a new tab)Last checked 15 October 2026
- Meta reduces Feed distribution of posts that request engagement. Source: Meta Transparency Centre (opens in a new tab)Last checked 15 October 2026
Up to 3 hashtags (Cohera's choice)
- LinkedIn's post limit is 3,000 characters. Source: LinkedIn Help (opens in a new tab)Last checked 15 October 2026
- LinkedIn's community policies forbid artificially increasing engagement and repetitive content. Source: LinkedIn Help (opens in a new tab)Last checked 15 October 2026
X
Up to 2 hashtags
- X recommends no more than 2 hashtags per post. Source: X Help Center (opens in a new tab)Last checked 15 October 2026
- Hashtags categorise posts and surface them in X search. Source: X Help Center (opens in a new tab)Last checked 15 October 2026
- X's authenticity policy treats excessive, unrelated or trend-jacking hashtags as spam. Source: X Help Center (opens in a new tab)Last checked 15 October 2026
- X's post limit is 280 characters, 4,000 on Premium. Source: X Help Center (opens in a new tab)Last checked 15 October 2026