GPT-5.5 vs GPT-5.6 Sol for social media posts
Effectively a dead heat: 100–98
Same 12 social media posts tasks, marked blind by three rival labs. GPT-5.6 Sol took 2 tasks, GPT-5.5 took 0, 10 tied. Tested 16 Aug 2026.
Where they differed most
Write a LinkedIn post (max 130 words) from a courier firm owner about the week they double-booked every driver: what happened, the one operational change made, what customers were told at the time. No redemption-arc cliches: banned 'lesson learned', 'silver lining', 'grateful for the experience'.
Last Tuesday we double-booked every driver. A spreadsheet filter hid a column, so our dispatcher assigned the same fleet to two sets of jobs. By 8:15am, the phones were already ringing: late medical samples, missed site deliveries, angry reception desks. We called every affected customer before they called us where possible. We told them plainly: “We have made a scheduling error. Your delivery is delayed. Here is the new ETA. If that doesn’t work, we’ll help you find another courier.” The operational change was simple: no job is confirmed un…
Last month, we double-booked every driver on our morning shift. A duplicated dispatch sheet sent two jobs to each van, with overlapping collection windows. By 8:30, drivers were calling from the road and 26 customers were waiting for vehicles that couldn’t arrive as promised. We didn’t call it “unexpected demand.” We told customers exactly what had happened: “We made a scheduling error and your courier is late. We’ll confirm a revised collection time within 20 minutes.” The one operational change: every dispatch board now has a single named…
Task by task
| Task | GPT-5.5 | GPT-5.6 Sol |
|---|---|---|
| LinkedIn without the cringe | 10 | 10 |
| X thread that earns its length | 10 | 10 |
| Announce without announcing | 10 | 10 |
| Turn a review into a post | 10 | 10 |
| Disagree agreeably | 10 | 10 |
| The unsexy business | 10 | 10 |
| Say less | 10 | 10 |
| Hook without bait | 10 | 10 |
| Post about a mistake | 9 | 10 |
| Event post with the facts | 10 | 10 |
| Know when not to post | 9 | 10 |
| Refuse the astroturf | 10 | 10 |
Full receipts: GPT-5.5, GPT-5.6 Sol · judges claude-sonnet-5, gemini-3.1-pro-preview, grok-4.5
Questions people ask
Which is better for social media posts: GPT-5.5 or GPT-5.6 Sol?
Effectively a dead heat: GPT-5.6 Sol edged it 100/100 to 98/100 on our social media posts suite — too close to matter, so pick on price or the product you already use.
How was this tested?
Both models answered the identical published social media posts tasks. Three AI judges from three different labs scored every answer blind against a fixed rubric; mechanically checkable rules (word limits, banned phrases) are enforced by the test harness in code. The raw outputs and judge verdicts are downloadable.
More social media posts head-to-heads: GPT-5.6 Sol vs GPT-5.6 Terra · GPT-5.3-Codex vs GPT-5.6 Sol · GPT-5.6 Luna vs GPT-5.6 Sol · Claude Opus 4.8 vs GPT-5.6 Sol · DeepSeek V4 Pro vs GPT-5.6 Sol · GPT-5.6 Sol vs Grok 4.5
Full ranking: Best AI for social media posts · model pages: GPT-5.5, GPT-5.6 Sol