Instagram caption generator
A scroll-stopping first line, a short body, a question to invite comments and a block of relevant hashtags. Images come in 4:5 portrait, the size that takes up the most space in the feed.
One idea in.Five posts out.
Type what you want to share. Get a caption for each platform and an image sized for every feed.
Writing your posts
This takes a few seconds.
Writing captionsMaking the imageSizing for each feed
Done for you
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Our team plans your content, designs every image in your brand style and publishes on all your platforms. You just approve.
- A monthly content plan built around your offers
- Custom designs in your colors, fonts and logo
- Posting on Instagram, Facebook, LinkedIn, X and Pinterest
- One contact for changes, no agency back-and-forth
Why use it
One post idea, five platform-ready versions
Each platform has its own rules for length, hashtags and image shape. This free AI social media post generator handles all of that: it writes the captions, suggests hashtags and creates the image, so you can stop rewriting the same post five times.
Written for each feed
Short and punchy for X, story-led for LinkedIn, hashtag-rich for Instagram and keyword-led for Pinterest.
Images in the right size
One AI image, cropped to 4:5, 1.91:1, 16:9 and 2:3 so nothing gets cut off in the feed.
You stay in control
Every caption is editable. Copy it, download the image and post it from your own account.
Stuck for ideas?
Social media post ideas to start with
Pick an idea, change the details to match your business and generate. Each one fills in the tool for you.
Promote
Engage
Build trust
Seasonal
Five tools in one
A caption generator for every platform
Choose one platform or all five. Each caption is written for how people actually read that feed.
LinkedIn post generator
Professional posts with a strong opening line, short paragraphs that are easy to read on mobile and three to five hashtags at the end. Good for announcements, hiring and thought leadership.
Facebook post generator
Friendly, conversational posts with a clear call to action and only a few hashtags, which suits how people read Facebook. Images come at the 1.91:1 link-preview size.
X (Twitter) post generator
One punchy post under 280 characters with one or two hashtags, and a 16:9 image. The Open X button fills the post in for you.
Pinterest pin description generator
A keyword-rich pin title and description written for Pinterest search, plus a tall 2:3 pin image that stands out in the grid.
Hashtags included
Every caption comes with hashtags picked for the topic and the platform, so you don't need a separate hashtag generator.
Create my postsHow to use the AI Social Media Post Generator
- Describe the postWrite one or two sentences about your offer, news or tip.
- Pick tone and platformsChoose how it should sound and where it will be posted.
- GenerateGet a caption and a correctly sized image for each platform.
- Copy and postEdit if needed, copy the caption, download the image and post.
Social media image sizes and caption limits
The sizes this tool exports, and the text limits each platform enforces.
| Platform | Image size | Ratio | Caption limit | Hashtags |
|---|---|---|---|---|
| 1080 × 1350 px | 4:5 portrait | 2,200 characters | Up to 30; 3 to 10 relevant ones work well | |
| 1200 × 630 px | 1.91:1 | 63,206 characters | 1 to 3, optional | |
| 1200 × 627 px | 1.91:1 | 3,000 characters | 3 to 5 | |
| X (Twitter) | 1600 × 900 px | 16:9 | 280 characters (free accounts) | 1 or 2 |
| 1000 × 1500 px | 2:3 portrait | Title 100, description 500 | Use keywords instead |
Platforms change their limits from time to time. We keep these values up to date.
Get more engagement
How to write social media posts that get engagement
The generator follows these rules for you. Keep them in mind when you edit a caption.
- Hook in the first lineFeeds cut captions short after a line or two. Put the most interesting part first so people tap "more".
- One idea per postA post that says one thing clearly gets more reactions than one that tries to say everything.
- Ask a real questionEnd with a question people can answer in a few words. Easy questions get more comments.
- Use a few relevant hashtagsPick hashtags your customers actually search for. A handful of specific tags beats thirty generic ones.
- Size the image for the feedA picture that is cropped badly looks careless. Portrait images take up more of the screen on Instagram and Pinterest.
- Finish with one clear actionTell people exactly what to do next: visit, reply, save or share. One call to action, not three.
Frequently asked questions
What is an AI social media post generator?
It is a tool that turns a short description of your post into finished captions and images using AI. You describe the idea once and get a version written for each platform, ready to copy and post.
Is the AI Social Media Post Generator free?
Yes. You can create 3 posts a day for free, with no signup. Each post includes captions for every platform you pick and an image sized for each one.
Which platforms does it support?
Instagram, Facebook, LinkedIn, X (Twitter) and Pinterest. Pick any combination before you generate.
Can it post directly to my accounts?
Not yet. Copy the caption, download the image and post from your own account. The "Open" button on each card takes you straight to the platform.
Why is the text on the image added separately?
AI image models often misspell words inside pictures. So the tool creates the image without text and then places your headline on top, which keeps every letter correct.
Can I edit the captions?
Yes. Every caption box is editable, and the character counter shows if you go over a platform's limit.
Can I use the images commercially?
Yes, you can use the generated images in your own posts and marketing. Avoid prompts that copy other brands' logos or real people's likenesses.
Do you store my posts?
No. Your input is sent to the AI to create the post and is not saved on our server. Images are not kept after you leave the page.
Why do different platforms get different captions?
People read each feed differently. A LinkedIn post can tell a short story, an X post has 280 characters, and Pinterest works like a search engine, so the same idea is written differently for each.
Can I use it as an Instagram caption generator only?
Yes. Untick the other platforms and the tool writes only the Instagram caption, hashtags and a 4:5 image. The same works for LinkedIn, Facebook, X or Pinterest on their own.
Does it write hashtags too?
Yes. Each caption includes hashtags chosen for your topic and the platform: more on Instagram, a few on LinkedIn and Facebook, one or two on X, and keywords instead of hashtags on Pinterest.
How many posts can I create?
You can create 3 posts a day for free. Each post can be rewritten per platform and you can ask for one new image. If you need posts every day, our team can create and publish them for you.
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