Social Media APIs for agents and developers.

Ship social features in minutes instead of months. One API to post, schedule, and engage across every platform at scale.

+ more
  • For developers, Creators, SaaS builders & AI agents
  • Post, schedule, and automate across unlimited accounts
  • X/Twitter, LinkedIn, Bluesky & more coming soon
schedule-post.tsTypeScript
const response = await fetch("https://api.synposter.com/v1/posts", {
  method: "POST",
  headers: {
    "x-api-key": "sk_live_your_api_key",
    "Content-Type": "application/json",
  },
  body: JSON.stringify({
    platforms: ["twitter", "linkedin", "bluesky"],
    content: "Just shipped our new feature!",
    mediaUrls: ["https://example.com/image.png"],
    scheduledFor: "2026-01-15T09:00:00Z"
  }),
});

Unified Social Media API

Three steps to go live

From signup to first post in under 3 minutes. No SDKs to install, no platform apps to register.

1

Get your API key

Sign up and grab your key. Takes 30 seconds. No approval process, no waitlist.

curl -X GET https://api.synposter.com/v1/health \
  -H "x-api-key: sk_live_your_key"

{ "status": "ok" }
2

Connect accounts

Link social accounts via OAuth. We handle token refresh, rate limits, and platform quirks.

curl -X POST https://api.synposter.com/v1/connect/twitter \
  -H "x-api-key: sk_live_your_key"

{ "auth_url": "https://twitter.com/oauth/..." }
3

Publish everywhere

One request. Every platform. You just added social media to your stack.

curl -X POST https://api.synposter.com/v1/posts \
  -H "x-api-key: sk_live_your_key" \
  -d '{ "platforms": ["twitter", "linkedin"], "content": "Hello world!" }'

{ "status": "published", "posts": 2 }

Everything you need to ship
social features

Skip months of integration work. Give your product full social media capabilities with one API.

Multi-Platform Publishing

Ship posts to X, LinkedIn, and more from a single call. No per-platform integrations to maintain.

Built-in Scheduling

Queue posts for later and we deliver them on time. Cancel or reschedule before they fire.

One API, Every Platform

One unified request shape covers every supported network. Skip each platform's SDK and quirks.

No OAuth Hassle

We handle OAuth flows, token refresh, and platform approvals. End users connect in seconds.

Multi-Account Fan-Out

Manage hundreds of connected accounts under one API key. Built for SaaS, agencies, and AI agents.

Developer-First

Predictable REST. Stable error codes. Full audit log. Designed by developers who hate platform docs.

FAQ

Common questions

Everything you'd want to know before integrating a unified social media API.

What is Synposter?

Synposter is a single REST API that publishes posts to X (Twitter), LinkedIn, and other social networks. You hit one endpoint, we handle each platform's OAuth, token refresh, media upload, and rate limits. It's built for SaaS products, agencies, and AI agents that need social posting without integrating each platform separately.

Which platforms does Synposter support?

X (Twitter) is live today. LinkedIn, Bluesky, Threads, Facebook, and Instagram are on the roadmap. The request shape stays the same across platforms, so adding a new one is a config change on your end, not a rewrite.

Do I need to register a developer app on each platform?

No. Your end users connect their accounts through Synposter's OAuth flow, which uses our platform credentials. You don't apply for developer access at X, LinkedIn, or anywhere else. That alone saves weeks of approval waits.

How do API keys work?

Generate a key from the dashboard and pass it as an x-api-key header on every request. Keys are stored as a SHA-256 hash on our side, so we can't recover one after generation, only invalidate and regenerate. Rotate freely.

What happens if one platform fails inside a multi-platform post?

Each account gets its own status in the response. A failure on X doesn't block the LinkedIn post from going through. You get a per-account result with a stable error_code (rate_limited, account_expired, platform_rejected, etc.) and a human-readable detail string, so retry logic is straightforward.

Can I send media — images, videos, GIFs?

Yes. Pass a public media URL in the same POST /v1/posts call and we fetch it and upload it to each platform. If hosting your own media isn't convenient, POST /v1/media gives you a presigned upload URL and a public URL to reference back, useful for scheduled posts where the file needs to stay reachable for hours.

Is there a free tier?

Yes — a one-time lifetime trial of 20 posts on the Free plan, no credit card. Paid plans start at $19/mo for 2,000 posts, with per-month quotas that reset each billing cycle.

Where is my data stored, and how secure is it?

OAuth access and refresh tokens are encrypted at rest with AES-256-GCM, with the encryption key held outside the database. API keys are hashed. Database connections are TLS-encrypted. Supabase enforces row-level security on every user-scoped table. We don't sell data and we don't use post content to train models.

Ship social posting today.

Free tier, no credit card. Generate an API key and publish your first cross-platform post in under three minutes.

Read the docs

20 free posts · No credit card · Cancel anytime