Free tool

AI caption generator — engaging posts for any platform

Generate captions for X (Twitter), Instagram, and LinkedIn using on-device AI. Pick a tone, describe your post, and get a caption with hashtag suggestions in seconds.

Describe your content

Tell the model what your post is about and pick a platform and tone.
Professional
Casual
Funny
Inspirational

Caption tips

Be specific about what's in the post.

Mention the mood or emotion you want.

Add context — audience, occasion, brand voice.

State the call-to-action you want at the end.

Platform norms

X (Twitter)

Concise, 1–2 hashtags, strong hook.

Instagram

Story-driven, up to 30 hashtags, clear CTA.

LinkedIn

Professional tone, 3–5 hashtags, industry insight.

Captions are generated locally in your browser. Nothing leaves your device.

Create engaging social media captions with on-device AI

The caption generator helps you write social posts that drive engagement. Whether you're posting on X, Instagram, or LinkedIn, it produces a caption tuned to that platform's length, tone conventions, and hashtag norms.

How it works

  1. 1. Describe your content. Tell the model what your post is about — a product photo, a team update, a quote, anything.
  2. 2. Pick a platform. X, Instagram, or LinkedIn — each has its own length and hashtag profile.
  3. 3. Set the tone. Professional, casual, funny, or inspirational.
  4. 4. Generate and refine. Copy the caption, regenerate for variations, or edit before posting.

Platform conventions

X (Twitter)

  • 280-character limit
  • Concise and punchy
  • 1–2 hashtags
  • Strong hooks

Instagram

  • Up to 2,200 characters
  • Story-driven content
  • 10–30 hashtags
  • Clear call-to-action

LinkedIn

  • 3,000-character limit
  • Professional tone
  • 3–5 hashtags
  • Industry insight

Why on-device AI

  • Private: your description never leaves the browser.
  • Free: no API costs, no rate limits, no signup.
  • Fast: after the first model load, generation is near-instant.

Frequently asked questions

Everything that matters about how these tools work, and what we do with your data.