How to Schedule Twitter/X Posts via API

Schedule tweets and Twitter/X posts programmatically using the SocialRails API. This guide covers character limits, supported content types, code examples, and best practices for automated Twitter posting.

Character Limits

• Standard tweets: 280 characters
• Twitter Blue/Premium: Up to 4,000 characters (long-form)
• URLs count as 23 characters regardless of actual length
• Images don't count against the character limit

Supported Content Types

API Example

# Schedule a tweet
curl -X POST https://socialrails.com/api/v1/posts \
  -H "Authorization: Bearer sr_live_YOUR_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "content": "Our new API! Check out the docs at socialrails.com/documentation",
    "platform": "twitter",
    "scheduled_for": "2026-03-15T14:00:00Z"
  }'

Scheduling a Thread

Use the thread array to create multi-tweet threads. Each item becomes a tweet, posted as replies in sequence.

curl -X POST https://socialrails.com/api/v1/posts \
  -H "Authorization: Bearer sr_live_YOUR_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "content": "Thread start",
    "platform": "twitter",
    "scheduled_for": "2026-03-15T14:00:00Z",
    "thread": [
      "1/ Here is why we built SocialRails",
      "2/ Managing 9 platforms from one API",
      "3/ Try it free at socialrails.com"
    ]
  }'

• 2-25 items per thread, each up to 4,000 characters
• Attach media per thread item with thread_media: {"0": ["media-key"], "2": ["media-key"]}
• Control pacing with thread_delay (0-60 minutes between items)

See the full Threading API reference for details.

First Comment

Automatically post a reply to your tweet right after it goes live. Use this for adding context, a call-to-action, or hashtags that you don't want in the main tweet.

curl -X POST https://socialrails.com/api/v1/posts \
  -H "Authorization: Bearer sr_live_YOUR_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "content": "We just shipped a huge update to our API!",
    "platform": "twitter",
    "scheduled_for": "2026-03-15T14:00:00Z",
    "first_comment": "Full changelog here: socialrails.com/changelog #buildinpublic"
  }'

The first comment is posted as a reply to the original tweet. Max 2,200 characters. Not available on thread posts.

Best Practices

• Optimal posting times: Weekdays 9-11am and 1-3pm in your audience's timezone
• Hashtags: Use 1-2 relevant hashtags (more can reduce engagement)
• Media: Tweets with images get 150% more retweets
• Thread timing: If posting a thread, space tweets 1-2 minutes apart
• Keep content concise, tweets under 100 characters see 17% higher engagement

Rate Limits

Twitter's own API limits apply in addition to SocialRails rate limits:

• 300 tweets per 3 hours per account
• 1,000 direct messages per 24 hours
• Media uploads: 15 per 15 minutes

SocialRails handles these limits automatically and will retry failed posts.