Schedule Tweets & Threads with AI Assistance

Connecting your X account

Connect your X (formerly Twitter) account to posterly through the Accounts page. posterly uses X's official OAuth 2.0 flow to authenticate, you'll be redirected to X to approve access, then returned to posterly. The connection grants posting permissions only; posterly never reads your DMs or modifies your profile.

Scheduling tweets

Open the Composer, select your X account, and write your tweet. posterly shows a live character counter, X allows 280 characters for standard accounts, 4,000 for Verified subscribers, and 25,000 for Premium subscribers. The AI can generate tweet-optimised captions that hit the right length and tone for the platform. Pick your date and time, or use "Next available" to find an open slot.

Posting with media and alt text

Attach up to 4 images or 1 video per tweet. Add alt text to each image to improve accessibility and reach, X surfaces alt-text-rich content in screen readers and visual search. posterly validates file sizes and formats against X's requirements automatically. Images can be JPEG, PNG, GIF, or WebP. Videos can be up to 140 seconds for standard accounts and longer for Premium users.

Polls

Create polls directly from the Composer. Add 2 to 4 options and pick a duration (5 minutes to 7 days). posterly schedules the poll for the time you choose and publishes it natively through X's API at the scheduled moment.

Reply controls

Choose who can reply to each scheduled tweet: everyone, only people you follow, or only people you mention. Reply controls are set per-post in the Composer.

Community posts

If you're a member of X Communities, posterly supports posting directly to a community. Add your community ID in the Community selector in the Composer. Note that X's API doesn't expose a list of your communities, so you'll need to enter the community ID manually (found in the community's URL on X).

Writing for how X actually ranks content

The public xai-org/x-algorithm repository shows that For You ranking is built around predicted actions, not just likes. Useful signals include replies, reposts, quotes, profile clicks, link clicks, shares, follows, dwell time, video quality views, and media interactions. Negative signals include not-interested, mute, block, report, and low dwell.

posterly helps you schedule posts built for those actions: sharp first lines, reply prompts, screenshot or demo proof, quote-worthy takes, useful threads, and follow-up replies. The goal is not to fill a calendar with sentences. The goal is to publish posts that make the right audience stop, respond, click your profile, share, or follow.

AI-powered tweet writing

posterly's AI is tuned for X's short-form style. It generates punchy, concise tweets that drive engagement, no fluff, no filler. You can generate multiple variations and pick the one that fits your voice. The AI can create tweet threads for longer-form content and help reframe winning posts with a fresh angle instead of copy-pasting the same thing until the feed learns to ignore it.

Best times to post on X

Use the AI Agent to find optimal posting windows. X engagement patterns tend to peak during commute hours and lunch breaks, but the AI analyses your specific audience and posting history to give personalised recommendations.