GPT-5.6 Sol vs Grok 4.6

What I tested — same prompt, two models

I run the same fixed prompt set through every new model the day it drops — same string, one shot, single HTML file out — and I score the result 0–10 on whether it ran, how close it hit the brief, and how good it looked. Below is what came out when I gave the exact same prompts to GPT-5.6 Sol and Grok 4.6, side by side, on 20 shared tasks inside the Agent Operating System.

Both models were given identical prompts inside the Agent Operating System — no help, no iteration, no "best of N" tricks. I run each prompt once, save the HTML file the model produces, and score it 0–10 on whether it ran, how close it hit the brief, and how good it looked. The scoring is mine. The verdicts below are pulled from my source comparison guides at agentos.guide where I publish every score and the reasoning behind it.

GPT-5.6 Sol · Benched on GoldieBench as the flagship Sol at medium reasoning, one-shot, then headless-playtested. In the Agent OS it's the top tier of a routed stack — Sol on the hard calls, Terra for the bulk, Luna for the everyday 90%.

Grok 4.6 · Benched on 16 skill-infused game builds, every one played through its full gameplay arc before scoring, then the broken ones were handed back to Grok 4.6 to repair itself.

Where GPT-5.6 Sol beat Grok 4.6

The tasks where I gave GPT-5.6 Sol a higher 0–10 score on the same prompt — with the actual commentary from my source guides.

Where Grok 4.6 beat GPT-5.6 Sol

The tasks where I gave Grok 4.6 a higher 0–10 score on the same prompt — with the actual commentary from my source guides.

Strengths & weaknesses I logged

Pricing & context — the spec sheet

The verdict — which should you pick?

Across 20 scored shared tasks, GPT-5.6 Sol averaged 8.12/10, beating Grok 4.6's 5.95/10 by 2.17 points. Pick GPT-5.6 Sol when the build has to ship on the first prompt and you can afford the trade-offs in the comparison below.

If you only run one of these inside your stack, the head-to-head average above is the call. If you can run both, my honest play is to wire GPT-5.6 Sol and Grok 4.6 both into the Agent Operating System and dispatch each from the kanban by task type — the hardest reasoning and code where being right beats being cheap → GPT-5.6 Sol, high-volume agent work where the per-token bill decides what you can afford to run → Grok 4.6. That's the same setup I run for the 4,000+ founders inside the AI Profit Boardroom.

FAQ — GPT-5.6 Sol vs Grok 4.6

Which is better, GPT-5.6 Sol or Grok 4.6?

On Goldie Bench, GPT-5.6 Sol averages 8.12/10 across the shared tasks, with 2 gold, 9 silver, 12 bronze overall. Grok 4.6 averages 5.95/10, with 1 gold, 0 silver, 0 bronze. GPT-5.6 Sol wins the head-to-head 18–2.

How much does GPT-5.6 Sol cost vs Grok 4.6?

GPT-5.6 Sol: GPT-5.6 shipped as three models — Luna ($1/$6 per M), Terra ($2.50/$15) and Sol ($5/$30) — each with a same-price pro variant that ships a higher default reasoning effort. All share a ~1.05M-token context window and are rated High capability. Benched here on the flagship, Sol, at medium reasoning effort via OpenRouter. Grok 4.6: xAI's August 2026 flagship. $2 per million input tokens and $6 per million output tokens on the standard tier (the Fast tier is double), which is roughly half what the other frontier models charge for the same Artificial Analysis Intelligence Index score of 61.

What's the context window for GPT-5.6 Sol vs Grok 4.6?

GPT-5.6 Sol has a 1,050,000 tokens context window. Grok 4.6 has a 500,000 tokens context window.

When should I pick GPT-5.6 Sol over Grok 4.6?

Pick GPT-5.6 Sol for: The hardest reasoning and code where being right beats being cheap; One-shot game/sim prototypes you want shippable on the first prompt; The flagship slot in a routed Agent OS — Sol for the hard 10%, Luna/Terra for the rest. The trade-off is the weaknesses we logged on the bench: Priciest tier on the bench at $30/M output — only worth routing the hardest 10% of work to Sol; Reasoning can eat the token budget on big open-world briefs (one 0-byte failure until the budget was raised, then it built clean).

When should I pick Grok 4.6 over GPT-5.6 Sol?

Pick Grok 4.6 for: High-volume agent work where the per-token bill decides what you can afford to run; Arcade, shooter and driving builds in one shot; Self-repair loops - it is unusually good at fixing a build when you hand it the real error. The trade-off is the weaknesses we logged on the bench: Flight models are its weak spot: both the flight sim and the dogfight shipped unflyable on the first pass; Two of sixteen game builds died on a hard error (a duplicate identifier and a bad computeBoundingSphere call); Worlds are lit and composed but usually untextured, so terrain reads as flat coloured planes.

How does Goldie Bench score GPT-5.6 Sol vs Grok 4.6?

Every demo on this page was built by Julian Goldie inside the Agent Operating System — same fixed prompt for both models, one shot, single HTML file out. Each result gets a 0–10 score on whether it ran, how close it hit the brief, and how good it looked. The highest score on each task gets gold; second gets silver; third gets bronze. See methodology for full provenance.

Related comparisons

Other head-to-heads using the same scoring system:

Full model pages: GPT-5.6 Sol · Grok 4.6 · back to the leaderboard