Zernio Review

Zernio is publishing infrastructure, not a scheduling dashboard. Your app or AI agent sends one request (POST /v1/posts) and Zernio publishes text, images or video to the connected accounts, now or at a scheduled time. The same API reads per-post and per-account analytics, handles direct messages, comments and reviews through one set of inbox endpoints, sends webhooks when a post publishes, a message arrives or an account disconnects, and manages ad campaigns through /api/v1/ads.

Setup is an API key (Bearer auth) plus official SDKs for Node.js, Python, Go, Ruby, Java, PHP, .NET and Rust, an OpenAPI 3.1 spec, and a hosted MCP server at mcp.zernio.com for Claude, ChatGPT and other agents; third-party apps connect with OAuth 2.1 and PKCE. Publishing targets listed on the homepage are Instagram, TikTok, YouTube, X, LinkedIn, Facebook, Threads, Pinterest, Bluesky, WhatsApp, Telegram, Discord, Snapchat and Google Business. Reddit posting is temporarily unavailable: Zernio says Reddit has blocked third-party apps from its API. The product was called Late (getlate.dev) until a rebrand; Zernio says existing API keys and old SDK packages keep working.

Zernio has no plans or seats; every feature is included and you pay per connected social account each month, on a graduated scale (each rate applies only to the accounts inside its band).

One connected profile on one platform counts as one account, and connects and disconnects are prorated daily. Posts are unlimited. Usage that is metered on top: the first 10,000 inbox messages sent each month are free, then $1 per 10,000 ($0.0001 each), and without a payment method sending pauses until next month; received messages do not count. The first 500 managed ads are free, then each active ad is metered (the per-ad rate was not shown on the page we read). X API calls are passed through at X's own rates with no markup: $0.005 per read, $0.015 per post or DM, $0.200 per post containing a URL. Phone numbers (from $3/mo), SMS (from $0.008 per US segment), calls, iMessage, RCS and WhatsApp templates are separate add-ons. No annual prices or free trial are listed; the free 2-account tier is the way to try it.

Prices checked on the vendor's pricing page on November 2, 2026. See Zernio pricing.

What Zernio lists on its homepage, pricing page, docs and October 2026 product update:

Zernio suits developers building a SaaS product, agency backend or AI agent that needs to post and read social data on behalf of many accounts, and who would rather not integrate each network's API and app review separately. The graduated per-account price is cheapest at the extremes: 2 accounts are free and large fleets fall to $1 per account.

If you want a visual calendar, approval workflow or content generation, Zernio does not provide them: Postiz gives an app plus API and can be self-hosted, and Blotato bundles AI image and video credits with posting. Between roughly 10 and 50 accounts, a flat plan such as Upload-Post can cost less.

Trustpilot shows a TrustScore of 4.8 from 208 reviews; recent reviewers mostly praise fast support and easy MCP or Claude setup, while a one-star review from October 2026 describes a refund dispute over a phone number for an unsupported country, which the company answered. Ryan Doser's review, written by a Blotato affiliate who did not run Zernio in production, calls the free tier generous and the API clean, but found Zernio's "40x faster than Blotato" rate-limit claim closer to 2x and says per-account pricing gets expensive past about 10 accounts. He also notes Capterra and Software Advice each show a single one-star review. Dupple's review (which uses affiliate links) likes the single request format and transparent pricing but warns there is no visual planner and that you inherit Zernio's uptime and network coverage.