AltAI · Create & plan
Free AI Caption Generator
Describe your post and get several caption options with hashtags, sized for the platform.
- Free
- No account
- Chats stay in your browser
What the Caption Generator does
The AltAI Caption Generator is a general AI chat model instructed to write social media captions. Describe your photo or video, the platform and the tone, and it returns several caption options with a call to action and a short set of relevant hashtags. It is free, needs no account, and your conversations stay in your browser.
It cannot see your images or videos, so the more you describe the post, the better the captions. It also has no access to live trend data, so it will not know which hashtags are popular this week. Check hashtags on the platform itself, keep captions honest about what you are offering, and adjust the wording so it sounds like your account.
Five options per request
Get a range of lengths and styles so you can pick or combine.
Fits each platform
Captions follow the norms of Instagram, TikTok, LinkedIn, X or Facebook.
Hashtag set included
A mix of broad and specific hashtags arrives separately from the caption.
Hooks and calls to action
Each caption opens with a hook and can end with a clear next step.
How to use the Caption Generator
- 1
Choose the Captions mode in AltAI.
- 2
Describe the post, the platform and the tone you want.
- 3
Pick a caption, check the hashtags on the platform and post it.
Example prompts
Click one to open AltAI in this mode with the prompt already sent.
- Instagram caption“Write Instagram captions for a photo of my homemade sourdough bread. Make them warm and a little funny.”Try this prompt
- LinkedIn post caption“Write a LinkedIn caption announcing that I started a new job as a UX designer.”Try this prompt
- Product launch“Write captions for a product launch post. Ask me about the product and platform first.”Try this prompt
- TikTok hook“Give me five short TikTok captions with strong hooks for a video about budget travel in Portugal.”Try this prompt
- Hashtags for my post“Suggest relevant hashtags for a post about indoor plant care for beginners.”Try this prompt
- Shorter caption“Make this caption shorter and punchier for X: [paste your caption]”Try this prompt
Tips for better answers
- Describe what is in the image: setting, mood, people, product.
- Say who follows you and what they care about.
- Ask for captions without emojis if that fits your brand.
- Check the length with the Caption Length Optimizer before posting.
Questions
Is the AltAI Caption Generator free?
Yes. The Caption Generator is a free mode in AltAI and needs no account. You can generate as many caption options as you like within normal fair-use limits. Your chats are stored in your browser rather than on an account.
Can it look at my photo or video?
No. The chat works with text only and cannot see images or videos. Describe the content instead: what is shown, where it was taken, the mood and anything you want highlighted. A clear two-line description usually gives much better captions than a single word.
Does it know which hashtags are trending?
No. It has no live access to social platforms or trend data. It suggests hashtags based on the topic you describe. Search each hashtag on the platform to see how active it is and whether the content under it matches your post before using it.
Which platforms does it write for?
It can write for Instagram, TikTok, Facebook, LinkedIn, X, YouTube, Pinterest and Threads. Tell it the platform so it can match length and tone. Character limits change over time, so check the final caption with AltFTool's Caption Length Optimizer or Tweet Character Counter.
Can I use these captions for a business account?
Yes. Give it your brand voice, product details and any words to avoid. Make sure the captions are accurate about prices, offers and claims, and follow the platform's rules on sponsored content and disclosures. The assistant does not know your business beyond what you tell it.
Ready when you are
Open AltAI in Caption Generator mode. Free, no account, and AltAI can be wrong, so check anything that matters.