The 6 Best Social Media Posting APIs in 2026 (MCP and REST)
A posting API used to mean REST endpoints for your code. In 2026 the caller is often an AI agent, and that splits the market in two. Both kinds priced from the vendors' own pages, same day.
“Social media posting API” used to mean one thing: a REST endpoint your code calls so you do not maintain eight platform integrations. In 2026 it means two things, because the caller changed — sometimes it is your code, and increasingly it is an AI agent. This page prices both kinds, from the vendors’ own pages, on the same day.
MCP or REST: pick your caller first
A REST API gives your code endpoints; you write the integration, store keys, and handle each platform’s quirks behind one vendor. An MCP server gives an agent tools: Claude, ChatGPT or Codex connects with OAuth, reads the tool descriptions like documentation, and schedules, replies or pulls analytics conversationally — with the vendor enforcing approval gates and pacing on its side. If a developer is on the payroll, REST is fine. If the “developer” is an assistant with a login, MCP is the difference between an afternoon and a sprint.
The six, priced
| Provider | Kind | Starts at | Free option |
|---|---|---|---|
| Social Magnum | MCP server (+app) | $24 /mo flat · 10 accounts | Free plan: 2 accounts, 15 posts /mo |
| Ayrshare | REST API | $149 /mo · 1 profile | None listed; 28-day trial on Launch |
| Upload-Post | REST API | $16 /mo · 5 profiles, unlimited uploads | Free: 10 uploads /mo, 2 profiles |
| Postiz | REST API + webhooks (+app) | $29 /mo hosted · 5 channels | Open source, self-host free |
| Blotato | Agent API + MCP (+AI studio) | $29 /mo · 1,250 AI credits, 20 accounts | 7-day trial; API excluded from trial |
| Buffer | REST API (+app) | rides plans: free to $10 /channel | Free plan: 3,000 requests /mo |
1 · Social Magnum — the MCP-first one (ours)
Social Magnum’s MCP server exposes 26 tools — scheduling, drafts, media, inbox replies, analytics, workspaces — with OAuth sign-in, per-token rate limits, approval gates and a public README documenting every tool an agent can call. It rides the normal flat plans: $24 a month for 10 accounts, $59 for 30, $119 for 70, AI included, free plan available. There is no separate API bill.
The honest limits: it is agent-first, not code-first — if you want raw REST endpoints for a backend service, the tools below are built for that — and it publishes to eight networks that do not include X, LinkedIn or Google Business.
2 · Ayrshare — the enterprise incumbent
Ayrshare is the established social API: thirteen networks, mature docs, webhooks, real support. The bill is enterprise too: Premium at $149 a month covers 1 profile, Launch at $299 covers 10, Business from $599 covers 30 with tiered per-profile rates above that.
The honest limit: the price of entry — a solo builder pays ten times Upload-Post’s rate for the first profile.
3 · Upload-Post — the cheapest pipe
Upload-Post does one job at the lowest price here: a posting API with a free tier (10 uploads a month, 2 profiles), then $16 a month for unlimited uploads on 5 profiles and $33 for 25, covering the mainstream networks including TikTok on paid tiers.
The honest limits: it is just the pipe — no calendar, inbox or approvals — and posting links on X costs a $19 a month add-on.
4 · Postiz — the open-source stack
Postiz pairs a scheduler with an API and webhooks, hosted from $29 a month (5 channels) to $99 (100 channels) — or free forever if you self-host the open-source build on your own server, which no one else on this page offers.
The honest limit: self-hosting means you run the infrastructure, and the product is the youngest here.
5 · Blotato — agent API plus AI studio
Blotato sells agent infrastructure (API plus an MCP server) bundled with AI image, video and voice generation, metered by credits: $29 a month for 1,250 credits and 20 accounts, $97 for 5,000 and 40, $499 for agencies. If AI video is part of your pipeline, nothing else here generates it.
The honest limits: the credit meter governs the AI half, and API access is excluded from the 7-day trial — you commit before you can test the API. Our full Blotato alternatives guide goes deeper.
6 · Buffer API — the rate-capped rider
Buffer includes API access with its ordinary plans — 3,000 requests a month on the free plan, 7,500 on Essentials, 15,000 on Team, per its pricing page. For light automation on top of a scheduler you already use, that is often enough.
The honest limit: the caps make it an automation companion, not an infrastructure API.
Or: the platforms’ own APIs
The zero-dollar option is real: Meta, TikTok, YouTube, Pinterest and the rest all publish official APIs. The cost is paid in kind instead — eight separate integrations, app reviews and permissions on each platform, token refresh and error handling forever, and a compliance surface that changes under you. Vendors on this page exist because that maintenance bill, priced in engineering hours, exceeds every subscription above.
How to pick
The short version
- 1
An AI agent is the caller: Social Magnum's MCP server — flat plans, documented tools, approval gates.
- 2
Your backend is the caller, budget-first: Upload-Post free to $16, then Postiz hosted at $29.
- 3
You want to own the infrastructure: Postiz, self-hosted.
- 4
Enterprise requirements and thirteen networks: Ayrshare, priced accordingly.
- 5
AI video generation in the same bill: Blotato, minding the credit meter.
- 6
Already on Buffer and need light automation: its bundled API caps may be all you need.
Related reading: the best Blotato alternatives, Social Magnum vs Buffer and the best social media schedulers in 2026.