AI caption generator
Paste what your post is about, pick a platform, and get 3 ready-to-post captions in seconds — for Instagram, TikTok, Facebook, X or LinkedIn. Free, no sign-up.
Need the image too? Try the AI Instagram post generator →
How to use our free AI caption generator
Describe your post in a line or two: the product, the moment or the offer. Specific beats vague — “single-origin pour-over is back this week” gets you better captions than “coffee”.
Pick a platform: Any platform, Instagram, TikTok, Facebook, X or LinkedIn. X captions stay under 280 characters, Instagram captions end with a few hashtags on their own line, and LinkedIn captions skip the gimmicks.
Add a tone if you want one — friendly, witty, professional, or any word that fits your brand. Leave it blank and the captions come out friendly.
Press Generate captions to get 3 different options. Copy your favorite with one tap, or press Write 3 more for a fresh set.
Why a good caption matters for social media growth
The photo stops the scroll; the caption decides what happens next. It tells people why the post matters, gives them a reason to comment, save or visit, and adds the words that search on Instagram and TikTok can match. A strong image with a weak caption is a missed chance.
Most small businesses don't run out of caption ideas — they run out of fresh ways to say them. Writing the fifth post of the week from a blank box is slow. Starting from three different drafts is faster, and seeing the angles side by side helps you spot the one that sounds like you. Whichever you pick, keep the shape simple: a first line that earns attention, one useful detail and a clear next step.
Frequently asked questions
Which platforms can it write captions for?
Instagram, TikTok, Facebook, X and LinkedIn, plus an Any platform option for a general caption. Each one gets its own style. X captions are written to stay under its 280-character limit, while Instagram allows up to 2,200 characters — but the drafts stay short on purpose, because the first line does most of the work.
Is the AI caption generator free?
Yes — it's free to use, with no sign-up and no email. Each run uses AI, so there's a fair-use limit: generate a lot of captions within a minute and it will ask you to wait briefly before the next batch.
Should I post the caption exactly as written?
Treat it as a strong first draft. Add the details only you know — a price, a date, a street name, a customer's words — and cut anything that doesn't sound like you. That small edit is what makes a caption feel human rather than generated.
Never write a caption again.
Postlefy writes captions like these in your brand's voice, designs the image, and posts to every platform for you — automatically, on autopilot.
Put it on autopilot — 50 free posts →