Posting API for Developers

One REST API to publish content across 17 social platforms. Post text, images, videos, and more with a single endpoint.

No credit card required · Full API access

Features

Everything you need

Multi-Platform Posting

Publish to Twitter/X, Instagram, LinkedIn, TikTok, Bluesky, Mastodon, and 11 more platforms from a single API call. No need to learn each platform's quirks.

Content Scheduling

Schedule posts for any future date and time. RelayAPI handles timezone conversion, queue management, and guaranteed delivery at the exact moment you specify.

Thread & Carousel Support

Create multi-part threads on Twitter/X and Bluesky, or carousel posts on Instagram and LinkedIn. Pass an array of content blocks and we handle the rest.

Platform-Specific Formatting

Automatically adapt content for each platform's constraints — character limits, hashtag placement, mention formatting, and link card generation.

Draft Management

Save posts as drafts, preview how they'll appear on each platform, and publish when ready. Collaborate with your team before anything goes live.

Post Status Tracking

Track every post through its lifecycle — queued, publishing, published, or failed — with detailed per-platform status and direct links to live posts.

Webhook Delivery Notifications

Receive real-time webhooks when posts are successfully delivered or fail on any platform. Build reactive workflows without polling for status.

Automatic Retry Logic

Transient platform failures are automatically retried with exponential backoff. Configure retry policies per post or rely on sensible defaults.

How It Works

Up and running in minutes

1

Get Your API Key

Sign up and generate your credentials in seconds.

2

Connect Social Accounts

Link platforms via OAuth with our guided setup flow.

3

Start Building

Use the API to publish, manage, and track content across all platforms.

Why Developers Choose RelayAPI

One Integration, 17 Platforms

Each social platform has its own auth flow, rate limits, and content rules. RelayAPI abstracts all 17 behind a single REST endpoint so you can focus on your product, not platform quirks.

Enterprise-Grade Reliability

Built on Cloudflare's global edge network with 99.9% uptime. Automatic retries, dead-letter queues, and detailed delivery reports mean your content reaches every platform — every time.

Developer-First Experience

Interactive API docs, TypeScript and Python SDKs, copy-paste code examples, and a responsive support team. Everything you need to integrate quickly and maintain confidently.

Quick Start

Start building in minutes

curl -X POST https:"color:#6a9955">//api.relayapi.dev/v1/posts \
  -H "Authorization: Bearer rlay_live_xxxxxxxx" \
  -H "Content-Type: application/json" \
  -d '{
    "content": "Excited to announce our new product launch! Check it out at https:">//example.com",
    "platforms": ["twitter", "linkedin", "bluesky"],
    "media": [
      { "url": "https:">//cdn.example.com/launch-banner.png", "alt_text": "Product launch banner" }
    ],
    "scheduled_for": "2026-04-01T14:00:00Z"
  }'

Frequently Asked Questions

Ready to Start Building?

Get your API key and start publishing across 17 platforms in minutes.

Start Building Free

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