Model comparison
GPT-5.6 Sol vs Grok 4.6
OpenAI against SpaceXAI, compared on context, price, and verified benchmark results.
Catalog record checked August 12, 2026; individual provider fields may change.
OpenAI
GPT-5.6 Sol
Frontier
SpaceXAI
Grok 4.6
Frontier
| Specification | GPT-5.6 Sol | Grok 4.6 |
|---|---|---|
| Provider | OpenAI | SpaceXAI |
| Tier | Frontier | Frontier |
| Context window | Winner: 1.05M | 500K |
| Max output | 128K | Not verified |
| Input / 1M tokens | $5 | Winner: $2 |
| Output / 1M tokens | $30 | Winner: $6 |
| Weights | Closed | Closed |
| Parameters | Not disclosed | Not disclosed |
| Reasoning levels | none, low, medium, high, xhigh, max | low, medium, high, xhigh |
| Modalities | text, image | text, image |
| Released | July 9, 2026 | August 12, 2026 |
| Artificial Analysis Intelligence Index [max] (2026-08-08) | 61 | 61 |
Prices are USD per million tokens at standard rates, excluding batch and caching discounts. Bold indicates the better figure where one is objectively better. Values we could not confirm from the provider are shown as “Not verified” rather than estimated.
Pricing tiers: GPT-5.6 Sol: Prompts above 272K tokens bill at 2× input and 1.5× output; cache writes are 1.25× the input rate. · Grok 4.6: Base tier is $2/$6 per million tokens; prompts at or above 200K tokens are priced at $4/$12. Cached input is $0.50 / $1.00. Web/X search tool calls bill separately.
GPT-5.6 Sol
OpenAI's flagship tier, aimed at the hardest reasoning and agentic work.
Best for
- Complex reasoning
- Agentic workflows
- Hard coding tasks
Watch out
25x Luna's input price — overspecified for routine generation. Sol Fast mode (where offered) is roughly ~2× price for ~2.5× speed — only enable when latency is the constraint. `gpt-5.2-chat-latest` / `gpt-5.3-chat-latest` shut down 2026-08-10 — migrate API chat traffic to Sol. ChatGPT Plus/Pro Chat got an Aug 6 Sol refresh + effort slider; Work/Codex/API July builds are unchanged.
Grok 4.6
SpaceXAI's current code and chat default — same $2/$6 list as Grok 4.5, with a 500K context window and image input.
Best for
- Coding agents
- Chat and knowledge work
- Cost-sensitive frontier work
Watch out
Token rates double above a 200K-token prompt. DeepSWE 1.1 best-effort for this family is the xhigh row at 66.7% (the catalog table rounds Pass@1 to 67%), not the higher-scoring medium config.
Benchmark
DeepSWE 1.1 in context
Both models shown against the wider field, with cost per completed task alongside the score.
Local leader
Claude Opus 5 [max]
74%
Rows shown
24
Highest published reasoning effort per model (not best Pass@1)
Snapshot date
2026-08-13
Mirrored from deepswe.datacurve.ai
Better is toward the top-right (higher pass rate, lower cost). X-axis is reversed to match DeepSWE’s public chart. v1.1 uses average cost / tokens / steps; v1 uses published medians.
| # | Model | Pass@1 | Cost / task | Tokens / task | Steps / task |
|---|---|---|---|---|---|
| 1 | Claude Opus 5 [max] | 74% | $11.84 | 118k | 99 |
| 2 | GPT-5.6 Sol [max] | 73% | $8.39 | 60k | 61 |
| 3 | Claude Fable 5 [max] | 70% | $21.63 | 119k | 88 |
| 4 | GPT-5.6 Terra [max] | 70% | $4.95 | 72k | 76 |
| 5 | Kimi K3 [max] | 69% | $4.65 | 82k | 98 |
| 6 | GPT-5.6 Luna [max] | 67% | $3.03 | 73k | 102 |
| 7 | GPT-5.5 [xhigh] | 67% | $7.23 | 46k | 82 |
| 8 | Grok 4.6 [xhigh] | 67% | $5.50 | 71k | 87 |
| 9 | Gemini 3.7 Flash [high] | 65% | $2.18 | 107k | 125 |
| 10 | DeepSeek V4-Pro [max] | 63% | $0.24 | 106k | 155 |
| 11 | Claude Opus 4.8 [max] | 59% | $13.22 | 135k | 120 |
| 12 | Qwen3.8-Max [xhigh] | 58% | $3.73 | 95k | 111 |
| 13 | Muse Spark 1.2 [xhigh] | 55% | $3.70 | 99k | 101 |
| 14 | Claude Sonnet 5 [max] | 54% | $26.40 | 214k | 268 |
| 15 | Grok 4.5 [high] | 54% | $2.42 | 36k | 61 |
| 16 | DeepSeek V4-Flash [max] | 53% | $0.10 | 108k | 153 |
| 17 | Muse Spark 1.1 [xhigh] | 53% | $2.36 | 74k | 96 |
| 18 | GPT-5.4 [xhigh] | 52% | $5.65 | 71k | 70 |
| 19 | Gemini 3.6 Flash [high] | 47% | $4.42 | 96k | 117 |
| 20 | GLM 5.2 [max] | 44% | $3.92 | 78k | 129 |
| 21 | Gemini 3.5 Flash [high] | 36% | $3.45 | 76k | 105 |
| 22 | Kimi K2.7 Code | 31% | $2.82 | 59k | 149 |
| 23 | Claude Sonnet 4.6 [high] | 30% | $5.52 | 76k | 134 |
| 24 | Gemini 3.1 Pro [high] | 12% | $2.14 | 28k | 76 |
DeepSWE “Best” picks the highest published reasoning effort per model (not the highest pass rate). Small gaps may not be statistically meaningful — confirm on deepswe.datacurve.ai.
Common questions
GPT-5.6 Sol vs Grok 4.6
Answered from the verified figures on this page rather than general guidance.
Is GPT-5.6 Sol or Grok 4.6 cheaper for input?
Grok 4.6 is cheaper at $2 per million input tokens, against $5 for GPT-5.6 Sol — roughly 2.5× the price. Output tokens usually dominate a real bill, so weigh the output rate more heavily than the input rate. These are base rates; GPT-5.6 Sol has tiered pricing: Prompts above 272K tokens bill at 2× input and 1.5× output; cache writes are 1.25× the input rate. Grok 4.6 has tiered pricing: Base tier is $2/$6 per million tokens; prompts at or above 200K tokens are priced at $4/$12. Cached input is $0.50 / $1.00. Web/X search tool calls bill separately.
Is GPT-5.6 Sol or Grok 4.6 cheaper for output?
Grok 4.6 is cheaper at $6 per million output tokens, against $30 for GPT-5.6 Sol — roughly 5.0× the price. Output tokens usually dominate a real bill, so weigh the output rate more heavily than the input rate. These are base rates; GPT-5.6 Sol has tiered pricing: Prompts above 272K tokens bill at 2× input and 1.5× output; cache writes are 1.25× the input rate. Grok 4.6 has tiered pricing: Base tier is $2/$6 per million tokens; prompts at or above 200K tokens are priced at $4/$12. Cached input is $0.50 / $1.00. Web/X search tool calls bill separately.
Which has the larger context window, GPT-5.6 Sol or Grok 4.6?
GPT-5.6 Sol accepts 1.05M tokens against 500K for Grok 4.6. This only matters if you routinely send very long documents or large codebases.
Do GPT-5.6 Sol and Grok 4.6 support the same reasoning levels?
GPT-5.6 Sol exposes none, low, medium, high, xhigh, max, while Grok 4.6 exposes low, medium, high, xhigh.
Should I use GPT-5.6 Sol or Grok 4.6?
Both sit in the frontier tier, so the choice usually comes down to price and context rather than capability. GPT-5.6 Sol suits complex reasoning; Grok 4.6 suits coding agents.
Next step
Choosing between them
Tier and workload decide this more reliably than a leaderboard position does.
If both sit in the same tier, the decision usually comes down to context window and output price rather than headline capability — output tokens dominate real bills.
If one is a step up within the same provider, the useful question is whether your hardest task actually fails on the cheaper tier. Most production volume — classification, extraction, summarization — does not.
Choosing a harness rather than a model — Cursor, Copilot, Claude Code, Muse Code, or Lovable? Compare agentic harnesses · Latest releases.