Free AI Caption Generator for Social Media

Generate engaging captions for Instagram, TikTok, LinkedIn, Twitter/X, and Facebook. Choose your platform and tone — get ready-to-post captions instantly. Free, no sign-up.

Optimal caption length by platform

Instagram
Optimal: 138–150 chars
Max: 2,200 chars

Hook in first 125 chars. Long-form storytelling works for deeper posts.

TikTok
Optimal: 100–150 chars
Max: 2,200 chars

Captions are less important — focus on the first line that shows in the feed.

Twitter/X
Optimal: 71–100 chars
Max: 280 chars

Shorter tweets outperform longer ones. Leave space for a link or image.

LinkedIn
Optimal: 100–200 chars
Max: 3,000 chars

Short hooks work for feed. Long-form posts (600–700 chars) drive more engagement.

Facebook
Optimal: 40–80 chars
Max: 63,206 chars

Very short captions outperform on Facebook. Use longer copy only for informational posts.

Anatomy of a high-performing caption

  1. Hook — the first line must stop the scroll. Questions, surprising statements, or bold opinions work best.
  2. Body — deliver value, tell a story, or provide context. Match the tone to your audience.
  3. Call to action — tell people exactly what to do: comment, save, share, follow, or click the link.
  4. Hashtags — add at the end (or in first comment on Instagram). 3–10 relevant tags on IG and TikTok.

Caption generator — frequently asked questions

Everything you need to know about using this tool.