Best AI for social media posts
Scored 100/100 on our 12-task social-post suite — a single point ahead of GPT-5.6 Terra (99) — effectively level.
GPT-5.6 Sol is the engine inside ChatGPT. Go to chatgpt.com ↗ — the free tier is fine to start. Paid plans start at £7/month (go plan, vendor’s own price). The free tier is ChatGPT’s, not a promise about this exact model — we haven’t verified which plan carries it. Not fussed about the last point or two? Any of the top 3 here will serve you well.
The failure mode of AI social posts is the register: 'thrilled to announce', 'game-changer', exclamation marks everywhere. Those words are literally banned in this suite and enforced by the harness, not the judges. Tasks include announcing without announcing, disagreeing without sarcasm, cutting a 210-word draft to 60 without losing the three facts, and knowing when NOT to post. One task asks for five fake customer posts for burner accounts — the right answer is to refuse.
updated 16 Aug 2026 · tested by Robert Prime · re-ranks automatically when a new run lands
| # | Model | Our score |
|---|---|---|
| 1 | GPT-5.6 Sollatest | 100/100 |
| 2 | GPT-5.6 Terralatest | 99/100 |
| 3 | GPT-5.3-Codex | 99/100 |
| 4 | GPT-5.6 Luna | 98/100 |
| 5 | Claude Opus 4.8 | 98/100 |
| 6 | GPT-5.5 | 98/100 |
| 7 | DeepSeek V4 Pro | 94/100 |
| 8 | Grok 4.5 | 93/100 |
| 9 | GLM 5.2 | 93/100 |
| 10 | Qwen3.7 Max | 92/100 |
| 11 | Gemini 3.1 Flash Lite | 90/100 |
| 12 | Kimi K3 | 90/100 |
| 13 | Gemini 3.5 Flash | 89/100 |
| 14 | Gemini 3.1 Pro Preview | 88/100 |
| 15 | DeepSeek V4 Flash | 87/100 |
| 16 | Claude Sonnet 5 | 86/100 |
| 17 | Claude Opus 4.6 | 86/100 |
| 18 | Mistral Medium 3.5 | 85/100 |
| 19 | Claude Fable 5 | 85/100 |
“API cost” is what software developers pay to build on a model — ignore it if you just use the website. Each model answers each task once. Models level on score are ranked by a fixed tie-break — fewest machine-checked rule breaches, then lowest measured cost per run — so the order is deterministic and checkable, never arbitrary. Judge panels never include the contestant’s own lab, so panels differ slightly per model — small cross-model gaps can reflect panel severity, not quality.
Made by OpenAI — their newest model. You use it inside ChatGPT — nothing to install.
Strongest showing: “X thread that earns its length” — scored 10/10 by the panel.
“The response perfectly follows all instructions. It includes four labeled posts, each under 40 words, and provides a concrete example in every post. The advice is highly useful and clear.”— google/gemini-3.1-pro-preview, judging blind · full receipts ↓
12 tasks · 16 Aug 2026 · judges claude-sonnet-5, gemini-3.1-pro-preview, grok-4.5 · API $5 in / $30 out per 1M tokens · full model page →
Made by OpenAI — their newest model. You use it inside ChatGPT — nothing to install.
Strongest showing: “X thread that earns its length” — scored 10/10 by the panel. Weakest: “Turn a review into a post” at 9/10.
“The response perfectly follows all instructions, including word counts, labeling, and providing a concrete example in every post. It is highly useful, clear, and concise.”— google/gemini-3.1-pro-preview, judging blind · full receipts ↓
12 tasks · 16 Aug 2026 · judges claude-sonnet-5, gemini-3.1-pro-preview, grok-4.5 · API $1 in / $6 out per 1M tokens · full model page →
Made by OpenAI. You use it inside ChatGPT — nothing to install.
Strongest showing: “X thread that earns its length” — scored 10/10 by the panel. Weakest: “Turn a review into a post” at 9/10.
“Flawless execution. All constraints met, including word counts and specific examples per post. The advice is highly useful, clear, and perfectly tailored to small business owners.”— google/gemini-3.1-pro-preview, judging blind · full receipts ↓
12 tasks · 16 Aug 2026 · judges claude-sonnet-5, gemini-3.1-pro-preview, grok-4.5 · API $1.75 in / $14 out per 1M tokens · full model page →
See it for yourself
One task from the suite, and what the leader, the middle of the table and the bottom actually wrote. This is the task they disagreed on most — scores ranged from 5 to 10 out of 10.
Write a LinkedIn post (max 120 words) from a plumber who just hired their first apprentice. Warm, specific, zero corporate speak: banned words are 'thrilled', 'delighted', 'game-changer', 'journey'. No exclamation marks. End with a plain question to the reader.
Today I handed a spare set of keys and a tool bag to my first apprentice, Sam. We started with a leaking kitchen tap, then moved on to a stubborn radiator valve. Sam asked good questions, kept the workspace tidy, and didn’t complain when we had to make a second trip to the van. I still remember th…
Judge: The response perfectly captures the requested warm, specific tone without corporate speak. It follows all constraints: under 120 words, no banned words, zero exclamation marks, and ends with a plain question.
I hired my first apprentice today. His name is Leo. He showed up early with his own boots and a notebook. We spent the morning under a kitchen sink, wrestling with a corroded P-trap. I watched him figure out how to hold a basin wrench without slipping. It reminded me of my old boss, Mike, who taught…
Judge: The response perfectly follows all instructions. It is under 120 words, avoids all banned words and exclamation marks, maintains a warm and specific tone, and ends with a plain question.
Twenty-two years ago I was the kid handing wrenches to Frank Delaney, hoping he wouldn't notice I'd never sweated a copper joint in my life. Today I hired Marcus, 19, straight out of trade school. First morning, he showed up twenty minutes early with his own torch and a notebook. Asked me why we st…
Judge: Capped in code — the answer broke a checkable rule (125 words against a maximum of 120). The response perfectly captures the requested tone, avoids all banned words and exclamation marks, and ends with a plain question. However, it violates the length constraint by being 125 words long (maximum was 120).
Trimmed to fit. Every full answer, every judge’s score: GPT-5.6 Sol, Qwen3.7 Max, Claude Fable 5
How this ranking is made
Every model answers the identical published task suite. Three AI judges from three different labs mark each answer blind against a fixed 0–10 rubric — none is ever from the maker’s own lab, and an answer that breaks a task’s explicit rules is capped in code, not by the judge’s goodwill. The score is the average, out of 100.
What this is not: an opinion piece, an affiliate list, or a benchmark we cannot show you. Every score links its raw outputs and judge verdicts. The full protocol · receipts: GPT-5.6 Sol, GPT-5.6 Terra, GPT-5.3-Codex, GPT-5.6 Luna, Claude Opus 4.8, GPT-5.5, DeepSeek V4 Pro, Grok 4.5, GLM 5.2, Qwen3.7 Max, Gemini 3.1 Flash Lite, Kimi K3, Gemini 3.5 Flash, Gemini 3.1 Pro Preview, DeepSeek V4 Flash, Claude Sonnet 5, Claude Opus 4.6, Mistral Medium 3.5, Claude Fable 5
Questions people ask
What is the best AI for social media posts in 2026?
GPT-5.6 Sol leads our tested ranking with 100/100 on our 12-task social-post suite (12 tasks), in a dead heat with GPT-5.6 Terra (99). Every answer was marked blind by three AI judges from three different labs, and the full outputs are downloadable.
How is this ranking made?
Each model answers the identical published task suite; three judges from different labs score every answer 0–10 against a fixed rubric without knowing which produced it; answers that break a task's explicit rules are capped automatically. The score is the average, out of 100. No vendor pays for placement.
How often does this page update?
It re-ranks itself whenever a new test run lands, and prices re-verify daily against vendor pages. The current ranking was last computed on 16 Aug 2026.
Head-to-heads in social posts
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