Zernio

What is Zernio and who is it for?

Zernio is a developer API for social media: one integration posts, schedules and pulls analytics across Instagram, TikTok, LinkedIn, X, YouTube, Facebook, Threads, Pinterest, Reddit, Bluesky and more. It is built for people who can make API calls, not for marketers who want a point-and-click scheduler.

The product was called Late until 2026, and its old address getlate.dev now redirects to zernio.com, with existing keys and integrations still working. Beyond posting, it covers comments and direct messages, ad campaigns on Meta, Google, LinkedIn, TikTok, Pinterest, X and OpenAI Ads, a Blogs API for WordPress and Shopify, and phone numbers for SMS, WhatsApp and calls. Zernio publishes an MCP server and SDKs so AI agents such as Claude Code and Cursor can post on your behalf. It doesn't write the posts itself, so an agent workflow still needs something to create the content.

How much does Zernio cost in the UK?

Zernio charges in dollars per connected social account each month: the first two are free, accounts 3 to 10 cost $6 each, 11 to 100 cost $3 each and every account after that costs $1.

Each rate applies only to accounts in its band, so 10 accounts cost $48 a month, 20 cost $78 and 100 cost $318. Every feature is included on every account. The extras are metered: messages you send are free up to 10,000 a month and then $1 per 10,000, managed ads are metered per active ad after the first 500, and X's own API charges are passed through at cost. Billing is monthly by card through Stripe, metered daily, and the pricing page doesn't mention VAT. Zernio is based in Girona, Spain, and offers GDPR paperwork through its trust portal on Enterprise terms.

Is Zernio's free plan any good?

For testing or a personal project, yes: two connected accounts are free with no card, including unlimited posts, analytics, 10,000 sent messages a month and the full API.

The limit is the number of accounts, not features. A blog, store or ad account counts as an account too, so a small business with Instagram, LinkedIn and a WordPress site would already pay $6 a month for the third. One independent reviewer, who uses a rival tool, called the free tier generous but found per-account pricing gets expensive past about 10 accounts compared with flat-rate competitors.

Zernio vs Buffer or Postiz: which is better?

Buffer suits people who schedule posts by hand in an app, Postiz suits teams who want an open-source scheduler they can host themselves, and Zernio suits developers who want to build posting into their own product or agent.

Zernio publishes its own comparison pages against Buffer, Ayrshare, Blotato, Publer, Postiz and Unipile. Its strength is breadth: messaging, ads and phone numbers sit in the same API as posting. The trade-off is that there is no scheduling app for non-technical users beyond what you build, though it connects to no-code tools such as n8n, Make and Zapier.

Is Zernio reliable and safe to connect accounts to?

Zernio says it uses official platform APIs only, states 99.7% uptime and over 2 million posts delivered, and runs on Vercel. Reviewers on Trustpilot mostly praise its quick support and ease of connecting it to AI tools.

The complaints are about change rather than reliability. Several Trustpilot reviewers say pricing and plans changed without notice around the rebrand, including a move from charging per profile to charging per connected account, and one says an Instagram account was removed after using the service. Anyone automating posts at volume should keep within each network's own rules, since accounts are still subject to the platforms' policies.